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Vocabulary
결정적이다

A2 adjective #3,000 most common 12 min read

결정적이다

gyeoljeongjeogida Top 3,000

Practice it Examples Notes & Tips 결정적이다 in 30 Seconds

Explanation 결정적이다 in your Level:

At the A1 level, '결정적이다' might seem a bit advanced, but you can think of it as a way to say 'very, very important' or 'the main reason.' Imagine you are playing a game and one person scores the winning goal. That goal is '결정적' (decisive). It is the reason the game ended that way. You don't need to use it in complex grammar yet. Just remember it as a word for 'the big thing' that makes a choice or a result happen. It's often used with words like '이유' (reason) or '순간' (moment). For example, '결정적인 이유' means 'the big reason.' Even though it's a long word, it's very useful for showing that something is special and changed the final result. Practice saying it slowly: Gyeol-jeong-jeok-i-da.

At the A2 level, you can start using '결정적이다' to describe your experiences and opinions. You can use it to talk about why you like something or why you did something. For example, '한국 드라마가 한국어를 배우는 결정적인 이유예요' (Korean dramas are the decisive reason I learn Korean). This shows that dramas weren't just 'one' reason, but the *main* reason. You can also use it in the past tense to talk about sports or movies you watched. '그 장면이 정말 결정적이었어요' (That scene was really decisive). This helps you move beyond basic adjectives like '좋다' (good) or '크다' (big) and start expressing more specific ideas about how things influence each other.

At the B1 level, you should be comfortable using '결정적이다' in various grammatical forms, especially the attributive form '결정적인' before nouns. You will see this word often in news articles and textbooks. It's important to understand the nuance: it's not just 'important,' but 'conclusive.' If you are writing an essay about the environment, you might say '플라스틱 사용 감소가 환경 보호에 결정적인 역할을 합니다' (Reducing plastic use plays a decisive role in environmental protection). This sounds much more professional than using '중요한' (important). You should also start noticing how it's used in debates to identify the 'decisive evidence' (결정적인 증거) that proves a point. It's a key word for building logical arguments in Korean.

At the B2 level, you should master the adverbial form '결정적으로' and understand how '결정적이다' differs from similar words like '치명적이다' (fatal) or '중대하다' (grave). You will use this word to analyze complex situations, such as business trends or historical events. For instance, you might discuss a '결정적인 타격' (decisive blow) in a market competition. You should also be able to use it in more abstract contexts, like '결정적인 차이' (decisive difference) between two philosophies or social systems. Your ability to use this word correctly will demonstrate that you can evaluate the relative importance of different factors and identify the most impactful one. It's a hallmark of a student moving toward advanced proficiency.

At the C1 level, '결정적이다' becomes a tool for nuanced academic and professional discourse. You will use it to discuss causality in depth. For example, in a legal or political analysis, you might argue about whether a specific event was truly '결정적' or merely '부차적' (secondary). You will encounter it in literature and high-level journalism to describe '결정적인 순간' (the decisive moment) in a character's development or a nation's history. You should also be aware of its usage in scientific contexts to describe '결정적인 실험' (conclusive experiments). At this level, you are not just using the word; you are weighing its applicability against other subtle descriptors to provide the most accurate analysis possible.

At the C2 level, your use of '결정적이다' should be indistinguishable from a native speaker's. You will use it to express philosophical or highly technical ideas. You might discuss '결정론' (determinism), which shares the same root, and how '결정적인 요인' (decisive factors) interact in complex systems like the economy or human psychology. You'll understand its rhetorical power in speeches and persuasive writing, using it to emphasize the finality and indisputability of your evidence or reasoning. You can also use it ironically or metaphorically in sophisticated literary contexts. Your mastery includes knowing exactly when *not* to use it, avoiding over-dramatization while maintaining the word's inherent weight and authority in your discourse.

Practice it Examples Notes & Tips

결정적이다 in 30 Seconds

Means 'decisive' or 'conclusive,' describing a factor that determines a final outcome.
Used in sports, law, business, and personal life to highlight critical turning points.
Commonly paired with nouns like '이유' (reason), '순간' (moment), and '증거' (evidence).
Functions as a descriptive verb (adjective) and must be conjugated or used as '결정적인'.

The Korean word 결정적이다 (Gyeol-jeong-jeok-i-da) is a powerful adjective that translates to 'decisive,' 'conclusive,' 'critical,' or 'pivotal.' At its linguistic core, it is composed of the noun '결정' (decision), the suffix '-적' (which transforms nouns into adjectives meaning '-ish' or '-like'), and the copula '이다' (to be). Together, they describe a state where an event, action, or piece of evidence has the ultimate power to settle a situation or determine an outcome. It is not merely about making a choice; it is about the magnitude of that choice's impact. When you call something '결정적,' you are saying that without this specific element, the result would have been entirely different. It represents the tipping point, the final piece of the puzzle, or the 'make or break' moment in any given narrative.

The Turning Point: In historical contexts or storytelling, this word identifies the specific moment when the tide turned. It describes an event that made a specific outcome inevitable.

이번 경기에서 그의 골은 승리에 결정적이었다. (His goal in this match was decisive for the victory.)

In daily life, Koreans use this word to emphasize importance. If you are looking for a house and find one with a perfect garden, that garden might be the '결정적인 이유' (decisive reason) why you buy it. In legal or investigative contexts, '결정적인 증거' (conclusive evidence) refers to the smoking gun that solves the case. It carries a weight of finality. Unlike the word '중요하다' (to be important), which simply denotes significance, '결정적이다' implies that this significance is the primary driver of the final result. It is the difference between a player being 'good' and a player being the 'reason' the team won the championship.

Evidence and Proof: Commonly used in news reports to describe DNA evidence or a witness statement that settles a long-standing mystery.

그의 실수는 팀의 패배에 결정적인 원인이 되었다. (His mistake became the decisive cause of the team's defeat.)

Furthermore, the word is frequently used in business and academia. A '결정적인 타격' (decisive blow) might refer to a competitor launching a superior product that forces a company out of the market. In science, a '결정적인 실험' (decisive experiment) is one that confirms a hypothesis beyond doubt. The nuance is always about the power to settle a debate or a struggle. It suggests that the matter is no longer up for discussion because this one factor has provided the answer. When you hear this word in a K-drama, it often precedes a major plot twist or the climax of a conflict.

Influence and Role: Often paired with '역할' (role) to describe how a person's contribution was the main reason for success.

그녀의 조언은 내가 유학을 가기로 마음먹는 데 결정적인 영향을 주었다. (Her advice had a decisive influence on my decision to study abroad.)

우리는 결정적인 순간에 용기를 냈다. (We showed courage at the decisive moment.)

Using 결정적이다 correctly requires understanding its grammatical flexibility as a descriptive verb (adjective). Because it ends in '-이다', it functions much like an adjective in English, but it must be conjugated according to the level of formality and the tense of the sentence. In its base form, it is used to state a fact about a situation. However, you will most frequently encounter it in its attributive form, 결정적인, which modifies a following noun. This is the most common way to say 'the decisive [noun]'. For example, '결정적인 순간' (decisive moment) or '결정적인 차이' (decisive difference). Understanding this pattern is key to sounding natural in Korean.

Attributive Form (Modifying Nouns): The pattern is '결정적인 + Noun'. This is used to describe the quality of the noun as being critical or conclusive.

그 증거는 범인을 잡는 데 결정적인 단서가 되었습니다. (That evidence became a decisive clue in catching the criminal.)

When using it at the end of a sentence to describe a subject, you must conjugate it. In polite informal speech (해요체), it becomes '결정적이에요'. In formal speech (하십시오체), it becomes '결정적입니다'. If you are talking about the past, use '결정적이었어요' or '결정적이었습니다'. This usage is common when summarizing a situation or giving an opinion on why something happened. For instance, after a long debate, you might say, '그 사람의 발언이 정말 결정적이었어요' (That person's statement was truly decisive). This summarizes the impact of the statement on the final outcome of the meeting.

Sentence Ending Form: Subject + 이/가 + 결정적이다 (conjugated). This emphasizes the state or nature of the subject.

이 문제는 우리 회사의 미래에 결정적입니다. (This issue is decisive for our company's future.)

Another advanced way to use it is with the adverbial form '결정적으로'. This modifies verbs and means 'decisively' or 'conclusively'. You might use this when describing how someone acted or how a situation changed. For example, '그는 결정적으로 행동했다' (He acted decisively). However, in many cases where English uses the adverb 'decisively', Korean speakers still prefer the adjective form '결정적인 역할을 하다' (to play a decisive role). This is a very common idiomatic structure. Instead of saying something 'decisively helped', you say it 'played a decisive role in helping'.

Adverbial Usage: 결정적으로 + Verb. This describes the manner in which an action was performed or how a result was achieved.

그 사건이 결정적으로 작용하여 계획이 취소되었습니다. (That incident acted decisively, so the plan was canceled.)

우리는 결정적인 차이를 만들어내야 합니다. (We must create a decisive difference.)

You will encounter 결정적이다 in a wide variety of settings, ranging from high-stakes news broadcasts to casual conversations about personal life choices. Its versatility makes it a staple of the Korean language. In the media, particularly in investigative journalism or legal dramas, the term '결정적인 증거' (conclusive evidence) is ubiquitous. You'll hear reporters say, '경찰은 결정적인 증거를 확보했습니다' (The police have secured conclusive evidence). This phrase signals to the audience that the mystery is nearing its resolution. It carries a sense of authority and finality that 'important evidence' (중요한 증거) simply lacks.

In Sports Media: Commentators use it to describe game-changing plays. A '결정적인 득점' is a goal that essentially ends the contest or ensures a win.

그 선수의 부상이 팀의 패배에 결정적인 영향을 미쳤습니다. (That player's injury had a decisive impact on the team's defeat.)

In business meetings, leaders use '결정적' to highlight the most critical factors in a strategy. If a company is deciding whether to enter a new market, the CEO might point to market research and say, '이 데이터가 결정적인 근거입니다' (This data is the decisive basis). It helps focus the team's attention on what truly matters. Similarly, in job interviews, candidates might describe a '결정적인 경험' (decisive experience) that led them to pursue their career path. This usage shows self-reflection and an understanding of one's own life trajectory. It tells the interviewer that the candidate doesn't just do things randomly but is driven by significant, life-altering moments.

In Personal Relationships: People use it to explain the 'why' behind major life changes, like breakups or marriages. '결정적인 이유' is the straw that broke the camel's back.

그의 한마디가 제 인생에 결정적인 계기가 되었어요. (His one word became a decisive turning point in my life.)

In academic or scientific writing, the word is used to describe findings that settle a hypothesis. A researcher might write, '이 실험 결과는 가설을 증명하는 데 결정적이다' (These experimental results are decisive in proving the hypothesis). Here, it replaces more common words like 'strong' or 'good' to provide a professional and precise tone. It implies that the evidence is so strong that no other conclusion can be drawn. Even in casual settings, like discussing a movie, you might say the ending was '결정적' because it explained everything that happened before. It is a word that brings clarity and resolution to any narrative or discussion.

In Legal Contexts: Used to describe '결정적인 증언' (decisive testimony) that changes the course of a trial.

이번 투표가 후보의 당선에 결정적인 역할을 할 것입니다. (This vote will play a decisive role in the candidate's election.)

그것은 결정적인 차이점입니다. (That is the decisive difference.)

One of the most common mistakes learners make with 결정적이다 is confusing it with the simple verb '결정하다' (to decide). While they share the same root, they function differently. '결정하다' is an action performed by a person (e.g., 'I decided to go'), whereas '결정적이다' is a description of a thing or situation (e.g., 'The weather was the decisive factor'). You cannot use '결정적이다' to say you made a choice. Another mistake is overusing it for minor details. Because it implies a 'conclusive' or 'critical' impact, using it for something trivial like 'the decisive reason I chose chocolate over vanilla' sounds overly dramatic or even sarcastic in Korean, unless that choice actually led to a life-changing event.

Misusing it as a Verb: Incorrect: 나는 유학을 결정적이다. (I am decisive study abroad.) Correct: 나는 유학을 결정했다. (I decided to study abroad.)

그 사건은 제 삶에 결정적인 영향을 주었습니다. (That incident had a decisive influence on my life.)

Another nuance mistake is failing to use the correct particle. When saying 'decisive for [something]', you should use the particle '에' or '에게'. For example, '성공에 결정적이다' (decisive for success). Using '를' or other object particles will result in an ungrammatical sentence. Furthermore, learners often forget the '적' part and just use '결정이다'. '결정이다' means 'It is a decision,' which is grammatically correct but has a completely different meaning. '결정적이다' describes the *quality* of being decisive. Ensure you include the '적' suffix when you want to describe the impact of something.

Particle Confusion: Use '에' to indicate what the thing is decisive for. Example: '승리에 결정적이다' (Decisive for victory).

그것이 결정적인 차이입니다. (That is the decisive difference.)

Lastly, be careful with the word order when using the attributive form. In English, we might say 'The moment was decisive,' but in Korean, '결정적인 순간' is much more common than '순간이 결정적이었다' in many contexts, especially when building a narrative. If you want to emphasize the noun, put '결정적인' right before it. If you want to conclude a thought, use the sentence-ending form. Also, avoid using '결정적이다' when you simply mean 'clear' (명확하다) or 'sure' (확실하다). '결정적' implies a causal link to an outcome, not just the clarity of a fact.

Overstatement: Avoid using it for trivial choices. It is reserved for factors that truly change the course of events.

그의 도움은 결정적인 힘이 되었습니다. (His help became a decisive strength.)

이것은 사건 해결의 결정적인 열쇠입니다. (This is the decisive key to solving the case.)

Understanding the synonyms and related terms for 결정적이다 will help you fine-tune your Korean expression. While '결정적이다' is the standard word for 'decisive,' there are other words that might be more appropriate depending on the level of intensity or the specific context you are in. For example, '중대하다' (to be important/grave) is often used for serious matters but lacks the 'conclusive' nuance. '확실하다' (to be certain) is used when there is no doubt about a fact, but it doesn't necessarily imply that the fact changes an outcome. By comparing these words, you can see where '결정적이다' fits in the spectrum of importance and causality.

결정적이다 vs. 중대하다: '중대하다' means 'serious' or 'grave' (e.g., a grave mistake). '결정적이다' means the mistake was the final reason for failure. '중대하다' focuses on the weight, while '결정적이다' focuses on the result.

그것은 결정적인 한 방이었습니다. (That was the decisive [final] blow.)

Another close synonym is '치명적이다' (to be fatal/lethal). This is often used for negative decisive factors. If someone makes a '결정적인 실수', it might just mean the mistake led to a loss. But if they make a '치명적인 실수', it implies the mistake was so bad it was 'fatal' to the project or person. '치명적' is much stronger and usually negative, though in modern slang, it can also mean 'lethally attractive'. Conversely, '관건이다' is a noun-based expression ('is the key') that functions similarly. You might say '이것이 성공의 관건이다' (This is the key to success), which is a very natural alternative to '이것이 성공에 결정적이다'.

결정적이다 vs. 확실하다: '확실하다' is about certainty. '이것은 확실한 증거다' (This is certain evidence). '결정적인 증거' means this evidence is what will win the trial. One is about truth, the other about impact.

그의 지원은 사업에 결정적인 도움이 되었습니다. (His support was a decisive help to the business.)

In formal writing, you might also see '사활이 걸리다' (life or death is hanging on it). This is an idiomatic way to say something is '결정적' for survival. For example, '이 프로젝트에 회사의 사활이 걸려 있다' (The company's survival depends on this project). This is even more intense than '결정적이다'. On the other hand, if you want to say something is 'pivotal' in a more neutral or structural way, you can use '중심적이다' (central). This suggests importance in the middle of a structure, whereas '결정적' suggests importance at the point of conclusion. Choosing the right word depends on whether you want to emphasize the weight, the certainty, the survival, or the finality of the factor.

Alternatives Table: - 중대하다 (Serious/Important)
- 확실하다 (Certain/Sure)
- 치명적이다 (Fatal/Lethal)
- 근본적이다 (Fundamental)

그것이 결정적인 요인이었습니다. (That was the decisive factor.)

우리는 결정적인 기회를 놓쳤습니다. (We missed a decisive opportunity.)

How Formal Is It?

Fun Fact

The root '결' (結) originally depicted the act of tying a knot to mark a finished task, which evolved into the concept of 'finishing' or 'deciding'.

Pronunciation Guide

UK /ɡjʌldʑʌŋdʑʌkida/

US /ɡjʌldʑʌŋdʑʌkida/

The primary stress is on the second syllable 'jeong', with a secondary emphasis on 'jeok'.

Rhymes With

열정적이다 (Yeol-jeong-jeok-i-da) 긍정적이다 (Geung-jeong-jeok-i-da) 안정적이다 (An-jeong-jeok-i-da) 감정적이다 (Gam-jeong-jeok-i-da) 상징적이다 (Sang-jing-jeok-i-da) 비판적이다 (Bi-pan-jeok-i-da) 효과적이다 (Hyo-gwa-jeok-i-da) 창의적이다 (Chang-ui-jeok-i-da)

Common Errors

Pronouncing 'gye' as 'ge' (don't forget the 'y' sound).
Weakening the 'ng' in 'jeong'.
Softening the final 'k' in 'jeok' too much.
Merging 'jeok' and 'i-da' into a single blurred sound.
Applying English word stress patterns (Korean is syllable-timed).

Difficulty Rating

Reading 3/5

Easy to recognize due to the '-적이다' ending, but requires understanding Hanja roots for depth.

Writing 4/5

Must remember to use '결정적인' for nouns and conjugate correctly for endings.

Speaking 3/5

Pronunciation is straightforward, but needs practice to sound natural in context.

Listening 3/5

Frequently heard in news and dramas, making it easy to pick up.

What to Learn Next

Prerequisites

결정 (Decision) 이유 (Reason) 중요하다 (To be important) 순간 (Moment) 증거 (Evidence)

Learn Next

효과적이다 (To be effective) 열정적이다 (To be passionate) 긍정적이다 (To be positive) 부정적이다 (To be negative) 구체적이다 (To be specific)

Advanced

필연적이다 (To be inevitable) 근본적이다 (To be fundamental) 치명적이다 (To be fatal) 독보적이다 (To be unrivaled)

Grammar to Know

-적이다 (Noun to Adjective)

역사 (History) -> 역사적이다 (To be historical)

-ㄴ/은 (Adjective to Attributive)

결정적이다 -> 결정적인 순간

-게/으로 (Adjective to Adverb)

결정적이다 -> 결정적으로 행동하다

~에 영향을 미치다

결정적인 영향을 미치다

~ㄴ/는 데 (In doing something)

성공하는 데 결정적이다

Examples by Level

이것은 결정적인 이유입니다.

This is the decisive reason.

Simple sentence using the copula '입니다'.

결정적인 순간이었어요.

It was a decisive moment.

Past tense polite informal form.

그의 골은 결정적입니다.

His goal is decisive.

Subject '골' (goal) with adjective.

결정적인 차이가 있어요.

There is a decisive difference.

Attributive form modifying '차이' (difference).

이것은 아주 결정적이에요.

This is very decisive.

Using the adverb '아주' for emphasis.

결정적인 증거가 필요해요.

I need decisive evidence.

Object '증거' (evidence) with adjective.

그 질문은 결정적이었어.

That question was decisive.

Past tense informal (반말).

결정적인 도움을 받았어요.

I received decisive help.

Attributive form modifying '도움' (help).

비가 온 것이 결정적인 원인이었어요.

The rain was the decisive cause.

Noun clause '비가 온 것' as subject.

그녀의 조언은 저에게 결정적이었어요.

Her advice was decisive for me.

Using '저에게' (to/for me).

결정적인 실수를 하지 마세요.

Don't make a decisive mistake.

Imperative form '하지 마세요'.

이 책은 제 인생에 결정적이었어요.

This book was decisive in my life.

Using '인생에' (in life).

우리는 결정적인 기회를 잡았습니다.

We caught the decisive opportunity.

Past tense verb '잡았습니다'.

결정적인 단서를 찾고 있어요.

I am looking for a decisive clue.

Present progressive '-고 있어요'.

그 사건은 팀에 결정적인 영향을 줬어요.

That incident had a decisive influence on the team.

Using '영향을 주다' (to give influence).

결정적인 선택을 해야 합니다.

You must make a decisive choice.

Obligatory form '-해야 합니다'.

이 실험 결과는 가설을 증명하는 데 결정적이다.

This experimental result is decisive in proving the hypothesis.

Using '-는 데' (in doing something).

정부의 지원이 사업 성공에 결정적인 역할을 했다.

Government support played a decisive role in the business's success.

Common phrase '역할을 하다' (play a role).

그는 결정적인 순간에 침착함을 유지했다.

He maintained his calm at the decisive moment.

Using '침착함' (calmness).

이 두 제품 사이에는 결정적인 차이가 있습니다.

There is a decisive difference between these two products.

Using '사이에는' (between).

그의 발언이 회의 결과에 결정적으로 작용했다.

His statement acted decisively on the meeting's result.

Adverbial form '결정적으로'.

결정적인 증거 없이는 그를 처벌할 수 없다.

Without decisive evidence, we cannot punish him.

Using '없이는' (without).

이번 투표는 나라의 미래에 결정적일 것입니다.

This vote will be decisive for the country's future.

Future tense '-을 것입니다'.

그녀의 노력은 우승에 결정적인 기여를 했다.

Her effort made a decisive contribution to the victory.

Using '기여를 하다' (to contribute).

그 사건은 두 나라의 관계에 결정적인 전환점이 되었다.

That incident became a decisive turning point in the relationship between the two countries.

Using '전환점' (turning point).

시장 조사가 이번 프로젝트의 방향을 결정적으로 바꿨다.

Market research decisively changed the direction of this project.

Adverb modifying the verb '바꿨다'.

결정적인 타격을 입은 회사는 파산 위기에 처했다.

The company, having suffered a decisive blow, faced a bankruptcy crisis.

Using '타격을 입다' (to suffer a blow).

그의 결단력은 위기 상황에서 결정적인 힘을 발휘했다.

His decisiveness exerted decisive power in a crisis situation.

Using '힘을 발휘하다' (to exert/show power).

과학자들은 마침내 결정적인 해결책을 찾아냈다.

Scientists finally found a decisive solution.

Using '찾아내다' (to find/discover).

그 증인의 증언은 재판에 결정적인 영향을 미쳤다.

The witness's testimony had a decisive influence on the trial.

Using '영향을 미치다' (to influence).

우리는 결정적인 순간을 놓치지 않기 위해 준비했다.

We prepared so as not to miss the decisive moment.

Using '-지 않기 위해' (in order not to).

이것은 그가 범인이라는 결정적인 증거가 된다.

This becomes decisive evidence that he is the criminal.

Noun clause '그가 범인이라는' modifying '증거'.

그 철학자의 이론은 근대 사상 형성에 결정적인 기여를 했다.

The philosopher's theory made a decisive contribution to the formation of modern thought.

Formal academic tone.

기술의 발전은 사회 구조의 결정적인 변화를 초래했다.

Technological advancement brought about a decisive change in social structure.

Using '초래하다' (to bring about/cause).

환경 요인이 생태계의 변화에 결정적으로 작용하고 있다.

Environmental factors are acting decisively on the changes in the ecosystem.

Present progressive adverbial usage.

이번 협상은 양국의 경제 협력에 결정적인 분수령이 될 것이다.

This negotiation will be a decisive watershed for economic cooperation between the two countries.

Metaphorical use of '분수령' (watershed).

그의 실패는 역설적으로 성공의 결정적인 발판이 되었다.

His failure paradoxically became a decisive stepping stone to success.

Using '역설적으로' (paradoxically).

유전적 요인이 성격 형성에 결정적인가에 대한 논쟁이 있다.

There is a debate about whether genetic factors are decisive in personality formation.

Question form within a noun clause '-ㄴ가에 대한'.

이 데이터는 가설의 타당성을 검증하는 데 결정적인 근거를 제공한다.

This data provides a decisive basis for verifying the validity of the hypothesis.

Formal research terminology.

그 사건은 역사의 흐름을 결정적으로 바꾸어 놓았다.

That incident decisively changed the course of history.

Using '-어 놓다' to emphasize the resulting state.

인간의 자유 의지가 운명에 결정적인 영향을 미칠 수 있는가?

Can human free will exert a decisive influence on destiny?

Philosophical inquiry.

그 작품의 미학적 가치는 결정적인 논란의 대상이 되어 왔다.

The aesthetic value of that work has been a subject of decisive controversy.

Using '-어 왔다' for continuing state.

경제적 불평등은 사회 통합에 결정적인 저해 요인으로 작용한다.

Economic inequality acts as a decisive hindering factor for social integration.

Sociological terminology.

언어는 사고의 틀을 형성하는 데 결정적인 역할을 수행한다.

Language performs a decisive role in forming the framework of thought.

Using '수행하다' (to perform/carry out).

이 발견은 물리학의 패러다임을 결정적으로 전환시킬 것이다.

This discovery will decisively shift the paradigm of physics.

Using '패러다임' and '전환시키다'.

기후 변화는 인류의 생존에 결정적인 위협이 되고 있다.

Climate change is becoming a decisive threat to human survival.

Global issue context.

그 정책의 실효성에 대한 결정적인 반증이 제시되었다.

A decisive counter-evidence regarding the effectiveness of that policy was presented.

Using '반증' (counter-evidence).

우연한 만남이 그의 예술 세계에 결정적인 영감을 불어넣었다.

A chance encounter breathed decisive inspiration into his world of art.

Literary expression '영감을 불어넣다'.

Common Collocations

결정적인 순간

결정적인 증거

결정적인 이유

결정적인 역할

결정적인 차이

결정적인 영향

결정적인 단서

결정적인 타격

결정적인 기회

결정적인 근거

Common Phrases

결정적으로 작용하다

— To act or function decisively in a situation.

그의 조언이 내 결정에 결정적으로 작용했다.

결정적인 한 방

— A final, decisive blow or move that ends a struggle.

선수는 마지막에 결정적인 한 방을 날렸다.

결정적인 고비

— A critical or decisive crisis point.

지금이 우리 사업의 결정적인 고비입니다.

결정적인 실수

— A mistake that determines the failure of an endeavor.

그의 결정적인 실수로 경기에 졌다.

결정적인 계기

— A decisive turning point or motivation.

유학은 내 인생의 결정적인 계기가 되었다.

결정적인 증언

— Decisive testimony in a legal case.

목격자의 결정적인 증언으로 범인이 잡혔다.

결정적인 득점

— A decisive goal or score in sports.

그의 결정적인 득점으로 팀이 우승했다.

결정적인 승부처

— The decisive point in a match or competition.

이번 3세트가 오늘 경기의 결정적인 승부처다.

결정적인 전환점

— A decisive turning point in history or life.

그 발명은 인류 역사의 결정적인 전환점이었다.

결정적인 패착

— A decisive bad move (often used in Go or politics).

그 정책은 정부의 결정적인 패착이었다.

Often Confused With

결정적이다 vs 결정하다

A verb meaning 'to decide'. '결정적이다' is an adjective meaning 'to be decisive'.

결정적이다 vs 단정적이다

Means 'to be assertive' or 'conclusive in speech', often implying a lack of flexibility.

결정적이다 vs 확정적이다

Means 'to be finalized' or 'fixed'. More about the state of a plan than the impact of a factor.

Idioms & Expressions

"결정적인 타격을 가하다"

— To deal a decisive blow to someone or something.

그 회사는 경쟁사에 결정적인 타격을 가했다.

Formal

"승패를 가르는 결정적인 순간"

— The decisive moment that separates victory from defeat.

지금이 바로 승패를 가르는 결정적인 순간입니다.

Neutral

"결정적인 열쇠를 쥐다"

— To hold the decisive key to a situation.

그가 이번 협상의 결정적인 열쇠를 쥐고 있다.

Neutral

"결정적인 한마디"

— A single word or sentence that settles everything.

그녀의 결정적인 한마디에 모두가 침묵했다.

Neutral

"결정적인 국면"

— A decisive phase or aspect of a situation.

전쟁은 이제 결정적인 국면에 접어들었다.

Formal

"결정적인 영향을 끼치다"

— To exert a decisive influence.

환경은 아이들의 성장에 결정적인 영향을 끼친다.

Neutral

"결정적인 근거를 대다"

— To provide a decisive basis or evidence.

그는 자신의 주장에 대해 결정적인 근거를 댔다.

Neutral

"결정적인 승기를 잡다"

— To seize the decisive opportunity for victory.

우리 팀은 후반전에 결정적인 승기를 잡았다.

Sports

"결정적인 대목"

— A decisive part or passage in a story or event.

소설의 이 부분이 주인공의 운명을 바꾸는 결정적인 대목이다.

Literary

"결정적인 차이점을 보이다"

— To show a decisive difference.

두 후보는 경제 정책에서 결정적인 차이점을 보였다.

Formal

Easily Confused

결정적이다 vs 중요하다

Both mean 'important'.

중요하다 is general; 결정적이다 implies it determines the final result.

공부는 중요하지만, 시험 성적은 대학 입학에 결정적이다.

결정적이다 vs 치명적이다

Both imply a huge impact.

치명적이다 is usually negative (fatal) or used for intense attraction.

그의 실수는 팀에 치명적인 타격이었다.

결정적이다 vs 확실하다

Both relate to certainty.

확실하다 is about the truth of a fact; 결정적이다 is about the impact of that fact.

그가 범인이라는 것은 확실하며, 이 DNA가 결정적인 증거다.

결정적이다 vs 주요하다

Both describe 'main' factors.

주요하다 is 'primary'; 결정적이다 is 'conclusive'.

관광은 그 나라의 주요한 산업이자 경제 성장의 결정적인 요인이다.

결정적이다 vs 중대하다

Both mean 'very important'.

중대하다 focuses on the gravity/seriousness of the matter.

국가의 안보는 중대한 문제이며, 이번 협상이 결정적인 영향을 미칠 것이다.

Sentence Patterns

이것은 결정적인 N입니다.

이것은 결정적인 이유입니다.

S은/는 결정적이었어요.

그의 골은 결정적이었어요.

A는 B에 결정적인 역할을 한다.

노력은 성공에 결정적인 역할을 한다.

결정적인 N이/가 되다.

그 증거는 결정적인 단서가 되었다.

결정적으로 작용하다.

환경 요인이 결정적으로 작용했다.

결정적인 저해 요인/발판.

그것은 성공의 결정적인 발판이 되었다.

Mixed

결정적인 순간에 ~하다.

결정적인 순간에 포기하지 마세요.

Mixed

결정적인 차이점은 ~이다.

결정적인 차이점은 가격입니다.

Word Family

Nouns

결정 (Decision)

결정력 (Decisiveness/Ability to decide)

결정권 (Right to decide)

결정론 (Determinism)

Verbs

결정하다 (To decide)

결정되다 (To be decided)

Adjectives

결정적이다 (Decisive)

미결정이다 (To be undecided)

확정 (Finalization)

판정 (Judgment)

단정 (Conclusion/Assumption)

해결 (Solution)

영향 (Influence)

How to Use It

frequency

High in media, sports, and formal discussions; moderate in daily casual speech.

Common Mistakes

Using '결정적이다' to mean 'I decided'. → 결정했다.
'결정적이다' is an adjective describing a thing. '결정하다' is a verb for a person's action.
Saying '결정적인 것' for everything. → 결정적인 이유 / 결정적인 순간.
While '것' is okay, using specific nouns like 'reason' or 'moment' is much more natural.
Using the particle '를' with '결정적이다'. → ~에 결정적이다.
Adjectives take '에' to show what they are decisive for, not the object particle '를'.
Confusing '결정적' with '단정적'. → Use '결정적' for impact, '단정적' for attitude.
'단정적' is often used to describe someone who talks as if they are always right, which can be negative.
Leaving out the '적' and saying '결정이다'. → 결정적이다.
'결정이다' means 'It is a decision'. '결정적이다' means 'It is decisive'.

Tips

Adjective vs. Verb

Remember that '결정적이다' is an adjective. It describes a state, not an action. Use '결정하다' for the action of making a choice.

Powerful Pairings

Pair '결정적인' with '순간' (moment), '이유' (reason), or '증거' (evidence) to sound like a native speaker instantly.

Don't Overuse

Save this word for truly impactful things. Using it for everything makes it lose its 'conclusive' power.

The 'Jeok' Sound

The 'k' in 'jeok' is a stop sound. Don't release a puff of air like an English 'k'; just close your throat.

Outcome Focused

Always ask yourself: 'Did this factor determine the final result?' If yes, '결정적이다' is the right word.

Sports Talk

In sports, use it to describe the winning goal or the play that changed the momentum of the game.

Professional Tone

In essays, replace '매우 중요한' (very important) with '결정적인' to sound more academic and precise.

News Keywords

When you hear '결정적인' on the news, pay close attention—the reporter is about to mention the most important fact.

Life Changes

Koreans use '결정적인 계기' to talk about life-changing moments. It's a great phrase for heart-to-heart talks.

Emphasis

You can add '정말' or '진짜' before '결정적이에요' to emphasize how critical the factor was.

Memorize It

Mnemonic

Think of 'Gyeol' as 'Goal'. A 'Gyeol-jeong' is the decision that hits the 'Goal'. If it's 'Gyeol-jeong-jeok', it's the 'Goal-hitting' decisive factor.

Visual Association

Imagine a judge hitting a gavel. That sound is '결정적이다'. It ends the case and makes the final decision.

Word Web

Decision Final Goal Evidence Turning Point Critical Impact Reason

Challenge

Try to find one '결정적인' reason for a decision you made today and write it in a sentence using '결정적인 이유는 ~입니다'.

Word Origin

Derived from the Hanja (Sino-Korean) roots '결' (結 - to tie/bind/finish) and '정' (定 - to fix/settle). The suffix '-적' (的) means 'target' or 'attribute'.

Original meaning: To tie or bind a matter into a fixed state.

Sino-Korean (Hanja-based)

Cultural Context

Be careful not to sound too arrogant by using '결정적' for your own opinions unless they are backed by strong facts.

While English speakers use 'decisive' mostly for people, '결정적이다' is used more broadly for situations and things.

The movie 'A Decisive Moment' (Korean title: 결정적 순간). Sports news headlines after a World Cup qualifying goal. Legal dramas like 'Stranger' (비밀의 숲) where '결정적인 증거' is a key plot point.

Practice in Real Life

Real-World Contexts

Sports Commentary

결정적인 골 (Decisive goal)
결정적인 패스 (Decisive pass)
결정적인 선방 (Decisive save)
결정적인 순간 (Decisive moment)

Legal/Criminal Investigation

결정적인 증거 (Decisive evidence)
결정적인 단서 (Decisive clue)
결정적인 증언 (Decisive testimony)
결정적인 물증 (Decisive physical evidence)

Business Strategy

결정적인 요인 (Decisive factor)
결정적인 역할 (Decisive role)
결정적인 차이 (Decisive difference)
결정적인 타격 (Decisive blow)

Personal Life/Decisions

결정적인 이유 (Decisive reason)
결정적인 계기 (Decisive turning point)
결정적인 영향 (Decisive influence)
결정적인 선택 (Decisive choice)

Academic Research

결정적인 근거 (Decisive basis)
결정적인 실험 (Decisive experiment)
결정적인 변화 (Decisive change)
결정적인 결과 (Decisive result)

Conversation Starters

"당신의 인생에서 가장 결정적인 순간은 언제였나요?"

"이 영화에서 가장 결정적인 장면이 무엇이라고 생각하세요?"

"한국어를 배우기로 한 결정적인 이유는 무엇인가요?"

"우리 팀이 이기기 위해 가장 결정적인 것은 무엇일까요?"

"이번 사건의 결정적인 증거가 무엇인지 아세요?"

Journal Prompts

내 삶에 결정적인 영향을 준 사람에 대해 써보세요.

내가 한 가장 결정적인 선택과 그 결과에 대해 설명해 보세요.

성공적인 하루를 보내기 위해 가장 결정적인 습관은 무엇인가요?

어떤 결정적인 계기로 인해 생각이 바뀐 경험이 있나요?

미래의 꿈을 이루는 데 결정적인 역할을 할 것은 무엇인가요?

Frequently Asked Questions

10 questions

Rarely. In English, we say 'He is a decisive person,' but in Korean, we use '결단력이 있다' (has decisiveness) for that. '결정적이다' usually describes situations, evidence, or reasons.

'결정적인' is an adjective used before nouns (e.g., 결정적인 순간), while '결정적으로' is an adverb used before verbs (e.g., 결정적으로 작용하다).

No, it can be negative. A '결정적인 실수' (decisive mistake) is a bad thing that leads to failure.

It sounds a bit dramatic for small things. Use '중요하다' for general importance and save '결정적이다' for things that truly change the outcome.

It is '결정적인 증거' (Gyeol-jeong-jeok-in jeung-geo).

Yes, especially when telling a story or explaining a big choice, like why you moved to a new city.

It means 'a decisive blow' or 'the final move' that wins a fight or a game.

It is a bit formal, but it's very common in everyday polite speech (해요체).

The most common opposites are '사소하다' (trivial) or '부차적이다' (secondary).

No, that would mean 'I am a decisive factor.' To say 'I have decided,' use '나는 결정했다'.