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C1 verb #10,000 most common 6 min read

obvidable

Top 10,000

Practice it Examples Notes & Tips obvidable in 30 Seconds

Explanation obvidable in your Level:

Obviate is a very big word! At this level, you don't need to use it, but you can think of it like this: Sometimes, you have a problem. You fix it before it happens. Or, you find a new way to do something, so the old way is not needed anymore. For example, if you have a robot to clean your house, you don't need to clean it yourself. The robot 'obviates' the need to clean. It makes the work go away. It is a formal word that grown-ups use in offices or in books to say 'we don't need this anymore because we have a better way.' Even though it is a C1 word, the idea is simple: making something unnecessary.

At the A2 level, you can understand 'obviate' as a formal synonym for 'make unnecessary'. Imagine you are planning a trip. If you buy your tickets online, you don't have to wait in line at the station. Buying online 'obviates' the need to wait in line. It is a word often found in business or technical news. It comes from Latin and means to 'get in the way' of a problem before it reaches you. When you use a computer to do math, it obviates the need for a calculator. It is a useful word to know when you want to sound very professional in your writing.

For B1 learners, 'obviate' is an excellent addition to your formal vocabulary. It means to anticipate a difficulty and act so that the difficulty never happens, or to make a requirement redundant. You will often see it in the phrase 'obviate the need for...' For instance, 'The new software obviates the need for manual data entry.' This means the software is so good that people no longer have to type in data by hand. It's more than just 'preventing'—it's about removing the reason for a task to exist. Use it when discussing improvements, efficiency, or strategic planning.

At the B2 level, you should start recognizing the nuance between 'obviate', 'prevent', and 'preclude'. To obviate is to perform a 'pre-emptive strike' on a problem or a requirement. It is heavily used in academic and professional contexts. If a company restructures, they might obviate certain roles. If a scientist finds a new method, it might obviate the need for expensive equipment. It is a transitive verb, meaning it needs an object. You don't just 'obviate'; you 'obviate the necessity of something'. It shows that you have a high level of English and can discuss complex systemic changes with precision.

As a C1 learner, 'obviate' should be part of your active vocabulary for formal essays and professional reports. It denotes a sophisticated level of prevention where the focus is on the systemic removal of a requirement. It is often used to describe how progress or innovation renders previous methods obsolete. For example, 'The advent of cloud computing has largely obviated the need for local server maintenance for small businesses.' Note the formal register: it is rarely used in spoken English unless the setting is quite serious or intellectual. It implies a strategic foresight that 'prevent' lacks.

At the C2 level, you appreciate 'obviate' for its precision in describing the neutralization of potentiality. It is a word that deals with the logic of necessity. In legal and philosophical discourse, to obviate a condition is to ensure that the condition can no longer arise or is no longer relevant to the framework. It is the perfect verb for describing 'elegant solutions' where the solution doesn't just fix a problem but makes the problem conceptually impossible. Its usage requires a delicate touch to avoid sounding overly pretentious, yet in the right context, it is irreplaceable for its clarity and economy of expression.

Practice it Examples Notes & Tips

obvidable in 30 Seconds

Obviate is a formal verb meaning to make something unnecessary or to prevent a problem through proactive planning.
It is most commonly used in technical, legal, and academic contexts to describe systemic improvements.
The word is typically followed by 'the need for' or 'the necessity of', targeting the requirement itself.
Understanding 'obviate' helps in articulating how innovation and strategy can simplify complex processes.

The verb obviate (often confused with the non-standard term 'obvidable') is a sophisticated linguistic tool used to describe the act of making something unnecessary or preventing a problem before it even occurs. It is not merely about stopping an event in progress; rather, it is about proactive elimination. When you obviate a need, you change the circumstances so that the need no longer exists. This is common in technical, legal, and formal academic writing where efficiency and foresight are valued.

Core Concept: To render unnecessary through prior planning or systemic change. It is the ultimate form of prevention.

The introduction of digital signatures will obviate the need for physical presence during the contract signing.

In professional settings, using this word signals a high level of literacy and a focus on strategic outcomes. For instance, a software engineer might suggest a refactor that obviates the need for complex error handling by removing the source of the error entirely. It is about elegance in problem-solving.

Formal Contexts: Used frequently in legal documents to describe clauses that remove obligations under specific conditions.

Strategic automation can obviate many of the risks associated with manual data entry.

Historically, the word comes from the Latin 'obviare', meaning to meet or withstand. Over centuries, the meaning shifted from physically meeting an opponent to intellectually meeting a problem before it arrives. This nuance is critical: you don't 'obviate' a person; you 'obviate' a requirement or a difficulty.

Linguistic Nuance: It acts as a transitive verb. You obviate [something]. It is a powerful way to describe systemic improvements.

A universal basic income might obviate the complex bureaucracy of means-tested welfare.

Mastering the use of obviate requires understanding its relationship with nouns like 'need', 'necessity', 'requirement', and 'difficulty'. It is a verb of removal. To use it correctly, identify a step in a process that is no longer required because of a new development.

Sentence Structure 1: The 'Need' Pattern: Subject + Obviate + the need for + Noun Phrase.

The new bypass will obviate the need for traffic to pass through the city center.

In academic writing, obviate is used to show how a new theory or discovery makes previous questions irrelevant. For example: 'The discovery of the Higgs boson did not obviate the search for new physics, but it did change the focus of the research.'

Sentence Structure 2: Technical Prevention: Subject + Obviate + Abstract Noun (e.g., risk, difficulty, expense).

Better insulation will obviate the high cost of heating during the winter months.

Consider its use in management: 'By addressing the employee's concerns early, the manager hoped to obviate any future grievances.' Here, it implies a proactive stance. The goal is to act so effectively in the present that the future trouble never materializes.

Sentence Structure 3: Modal Verbs: Often used with 'might', 'would', 'could', or 'should' to discuss potential benefits.

Such a move would obviate the necessity of a second round of voting.

While you might not hear obviate at a casual Sunday brunch, it is a staple in specific professional ecosystems. Understanding these domains helps in recognizing the word's intent.

Domain 1: Law and Regulation: Lawyers use it to describe how one legal provision might make another unnecessary. 'The settlement obviates the need for a trial.'

Compliance with the new standards will obviate further regulatory scrutiny.

In technology circles, particularly in software development and system architecture, 'obviating' a feature or a bug is the gold standard. It means the system has been redesigned so that the previous complexity is gone.

Domain 2: Medicine and Science: Used to discuss treatments that remove the need for surgery. 'Early diagnosis can obviate the need for invasive procedures.'

The vaccine's efficacy could obviate the risk of a widespread epidemic.

In political discourse, you might hear a commentator say that a certain policy 'obviates the core argument of the opposition.' This means the policy addresses the underlying issue so thoroughly that the opposition's complaints are no longer valid.

Domain 3: Engineering and Design: Engineers use it when a design improvement removes a failure point. 'The integrated sensor obviates the need for external monitoring.'

Even advanced learners and native speakers sometimes stumble when using obviate. The most common error is confusing it with 'obvious' or 'oblivious' due to phonetic similarity.

Mistake 1: Confusing with 'Obvious': 'Obviate' is a verb meaning to prevent; 'Obvious' is an adjective meaning clear. They are not interchangeable.

Incorrect: He made the plan obviate. Correct: He obviated the need for a plan.

Another mistake is using 'obviate' to mean 'to make clear'. While 'obviate' and 'obvious' share a root, their meanings have diverged significantly. You cannot 'obviate a point' if you mean 'make a point clear'.

Mistake 2: Redundancy: Saying 'obviate away' or 'obviate out'. 'Obviate' already contains the sense of removal.

Incorrect: This will obviate away the costs. Correct: This will obviate the costs.

Finally, ensure the subject is the thing that does the preventing. 'The new technology obviates the need' is correct. 'I obviate the need' is grammatically correct but less common than attributing the action to the solution itself.

Choosing between obviate and its synonyms depends on the level of formality and the specific nuance of 'prevention' you wish to convey.

Obviate vs. Preclude: 'Preclude' means to make something impossible. 'Obviate' means to make something unnecessary. They are close but 'obviate' focuses on the lack of need.

His injury precluded him from playing. The win obviated the need for a rematch.

'Forestall' is another synonym, but it implies acting in advance to stop an event. 'Avert' is usually used for disasters (averting a crisis). 'Obviate' is the most clinical and strategic of the group.

Obviate vs. Prevent: 'Prevent' is a general term. 'Obviate' is specific to removing a requirement through foresight.

Locking the door prevents theft. The new keyless system obviates the risk of losing keys.

How Formal Is It?

Fun Fact

The word 'obvious' comes from the same root 'ob-via', meaning 'lying in the way', hence something you can't miss because it's right in front of you on the road.

Pronunciation Guide

UK /ˈɒb.vi.eɪt/

US /ˈɑːb.vi.eɪt/

Primary stress is on the first syllable: OB-vi-ate.

Rhymes With

deviate alleviate abbreviate appropriate (verb) negotiate initiate exfoliate radiate

Common Errors

Pronouncing it like 'obvious-ate'.
Stressing the second or third syllable.
Confusing the 'v' sound with a 'b' sound in some accents.
Shortening the final 'ate' to 'it'.
Confusing it with 'obliviate' (a fictional word from Harry Potter).

Difficulty Rating

Reading 8/5

Common in high-level journalism and academic texts.

Writing 9/5

Requires precise knowledge of transitive verb structures.

Speaking 9/5

Rarely used in speech; can sound overly formal.

Listening 7/5

Easy to confuse with 'obvious' if not listening carefully.

What to Learn Next

Prerequisites

prevent necessary eliminate anticipate requirement

Learn Next

preclude forestall redundancy mitigate circumvent

Advanced

teleological ontological moot inequity volatile

Grammar to Know

Transitive Verbs

You must obviate *something* (e.g., 'obviate the need').

Gerunds as Subjects

Using a dishwasher obviates the need for hand-washing.

Infinitive of Purpose

The law was passed to obviate future confusion.

Passive Voice

The need for a trial was obviated by the settlement.

Modal Verbs for Possibility

This change might obviate the current difficulties.

Examples by Level

A good map can obviate the need to ask for directions.

A map makes asking for help not needed.

Obviate is the action word (verb).

The rain obviated the need to water the garden.

The rain did the work for us.

Past tense: obviated.

Does this tool obviate the need for a hammer?

Do I still need a hammer?

Question form.

I hope this app will obviate my money problems.

The app will stop the problems.

Future tense with 'will'.

Eating healthy might obviate the need for medicine.

Healthy food keeps you away from doctors.

Modal verb 'might'.

The new rules obviate the old rules.

The old rules are gone.

Present tense.

He obviated the risk by being careful.

He stopped the danger early.

Subject-Verb-Object.

Can we obviate the cost of the trip?

Can we make the trip free?

Modal 'can'.

The internet obviates the need for paper encyclopedias.

We don't need big books anymore.

Third-person singular 's'.

A warm coat obviates the discomfort of the cold.

The coat stops the cold feeling.

Abstract object: discomfort.

This shortcut obviates the long walk around the lake.

The short path makes the long path unnecessary.

Focus on efficiency.

Does having a car obviate the use of the bus?

Do you stop using the bus?

Gerund 'having' as subject.

The agreement obviated any further arguments.

The deal stopped more fighting.

Past tense.

Smart lights obviate the need to flip switches.

You don't have to touch the wall.

Plural subject.

Will the new bridge obviate the ferry service?

Will the boat stop running?

Future question.

The update obviates the previous security flaws.

The update fixes the old holes.

Technical context.

The new legal clause will obviate any future disputes over ownership.

The law stops future fights.

Formal register.

Automated systems often obviate the need for repetitive human labor.

Machines do the boring work.

Adverb 'often' placement.

Her quick thinking obviated a potentially disastrous situation.

She stopped a big problem fast.

Descriptive adjective 'potentially disastrous'.

Does this new evidence obviate the original hypothesis?

Does the new info make the old idea wrong?

Scientific context.

Providing clear instructions can obviate many common mistakes.

Good rules stop errors.

Gerund phrase as subject.

The settlement was designed to obviate the expense of a trial.

The deal saves money.

Passive voice 'was designed to'.

Digital banking has obviated the necessity of visiting a branch.

You don't have to go to the bank.

Present perfect tense.

We hope this measure will obviate the risk of infection.

We want to stop the sickness.

Future intention.

The implementation of the new policy obviates the need for a separate committee.

The policy makes the group redundant.

Complex noun phrase 'implementation of the new policy'.

Advanced planning can obviate the most common logistical nightmares.

Planning stops big travel problems.

Metaphorical 'nightmares'.

The presence of a security guard obviates the need for an alarm system.

The guard is enough.

Logical substitution.

Will the rise of AI obviate the need for human translators?

Will robots replace people?

Speculative future.

The treaty was intended to obviate the possibility of another conflict.

The deal stops war.

Infinitive of purpose.

The use of pre-cast concrete obviates much of the on-site construction time.

Pre-made parts save time.

Technical efficiency.

The software's intuitive design obviates the necessity for extensive training.

It's so easy you don't need to learn.

Possessive 'software's'.

Strict adherence to safety protocols obviates the likelihood of accidents.

Following rules stops crashes.

Gerund subject 'adherence'.

The recent court ruling may obviate the need for further legislative action.

The judge's decision might stop new laws.

Epistemic modality 'may'.

Strategic diversification can obviate the risks inherent in a volatile market.

Variety stops market danger.

Advanced vocabulary 'inherent', 'volatile'.

The integration of these two departments will obviate redundant administrative tasks.

Combining groups stops double work.

Business jargon 'redundant'.

The vaccine's high efficacy obviates the requirement for booster shots in the short term.

The shot is so good you don't need more yet.

Precision in time 'in the short term'.

Does the existence of a backup system obviate the need for rigorous testing?

Does having a spare mean you don't have to check?

Rhetorical question.

The new design obviates the structural weaknesses found in previous models.

The new way is stronger.

Engineering context.

Judicious financial management can obviate the necessity for external borrowing.

Good money handling stops debt.

Formal adjective 'judicious'.

The discovery of a cheaper catalyst could obviate the high costs of the reaction.

A new chemical makes it cheaper.

Conditional 'could'.

The ontological argument seeks to obviate the need for empirical evidence of the divine.

The logic makes proof unnecessary.

Philosophical register.

The pervasive nature of the surveillance obviates the possibility of true privacy.

Watching everywhere stops privacy.

Sociopolitical commentary.

Such a comprehensive reform would obviate the systemic inequities currently plaguing the sector.

Fixing the system stops the unfairness.

Abstract systemic objects.

The inherent redundancy in the aircraft's systems is intended to obviate catastrophic failure.

Double systems stop crashes.

Technical precision.

Does the advent of AGI obviate the teleological justifications for human labor?

Do smart robots make the 'purpose' of work go away?

Highly academic 'teleological'.

The sheer scale of the project obviates any attempt at centralized management.

It's too big to control from one place.

Logical consequence.

The linguistic shift has obviated the distinction between these two formerly discrete terms.

The two words now mean the same.

Linguistic register.

His resignation was a tactical move to obviate the ignominy of a public dismissal.

He quit to avoid being fired publicly.

Nuanced social strategy.

Synonyms

forestall preclude avert bypass eliminate counteract

Antonyms

necessitate require entail

Common Collocations

obviate the need

obviate the necessity

obviate the risk

obviate the problem

obviate difficulties

completely obviate

largely obviate

obviate potential

obviate further

obviate expense

Common Phrases

obviate the need for

— To make something no longer necessary.

The new bypass will obviate the need for heavy traffic in town.

obviate the necessity of

— To remove the requirement for something.

The agreement obviates the necessity of a formal trial.

obviate a risk

— To prevent a danger before it happens.

Early intervention can obviate the risk of heart disease.

obviate a difficulty

— To remove a hurdle in a process.

The new software obviates the difficulty of data migration.

obviate a problem

— To ensure a problem doesn't arise.

Better design can obviate maintenance problems.

obviate a requirement

— To make a rule or condition unnecessary.

The waiver obviates the requirement for a visa.

obviate an expense

— To save money by removing a cost.

Working from home obviates the expense of commuting.

obviate a conflict

— To prevent a fight or disagreement.

Diplomacy can obviate the need for military action.

obviate a delay

— To prevent things from taking too long.

Pre-registration obviates delays at the entrance.

obviate a crisis

— To stop a disaster from occurring.

Strategic reserves can obviate an energy crisis.

Often Confused With

obvidable vs obvious

An adjective meaning clear; 'obviate' is a verb meaning prevent.

obvidable vs oblivious

An adjective meaning unaware; has no relation to 'obviate'.

obvidable vs alleviate

Means to make pain or a problem less severe, but not necessarily to remove it entirely like 'obviate'.

Idioms & Expressions

"nip in the bud"

— To stop something at an early stage, effectively obviating future growth.

We need to nip these rumors in the bud to obviate a PR crisis.

informal

"clear the way"

— To remove obstacles, which can obviate the need for complex maneuvers.

The new law clears the way for investment and obviates red tape.

neutral

"cut the Gordian knot"

— To solve a complex problem with a bold action, often obviating traditional steps.

His decision to merge the companies cut the Gordian knot and obviated years of competition.

literary

"pre-empt the move"

— To act before someone else, obviating their strategy.

By lowering prices, they pre-empted the competitor's move and obviated the loss of market share.

business

"render moot"

— To make a point irrelevant, often by obviating the underlying issue.

The court's decision rendered the previous arguments moot and obviated further debate.

legal

"save a rainy day"

— Though usually about money, acting now to obviate future hardship.

Investing in infrastructure now will save a rainy day and obviate future repairs.

informal

"an ounce of prevention is worth a pound of cure"

— The philosophy of obviating problems rather than fixing them.

We focus on maintenance because an ounce of prevention obviates a pound of expensive repairs.

neutral

"bridge the gap"

— To connect two things, which might obviate the need for a middleman.

The app bridges the gap between farmers and buyers, obviating the need for distributors.

neutral

"kill two birds with one stone"

— To solve two problems at once, often obviating a second action.

This policy kills two birds with one stone and obviates the need for a separate environmental bill.

informal

"write off"

— To dismiss something as unnecessary or lost, effectively obviating it from the books.

They decided to write off the old debt, obviating the need for further collection efforts.

business

Easily Confused

obvidable vs alleviate

Phonetic similarity and both deal with problems.

Alleviate makes a problem better (less pain); obviate makes the problem go away or unnecessary.

Aspirin alleviates a headache. A healthy lifestyle might obviate the need for aspirin.

obvidable vs preclude

Both mean to stop something.

Preclude makes something impossible; obviate makes it unnecessary.

The rain precluded the game. The roof obviated the need to cancel the game.

obvidable vs obliterate

Both start with 'ob' and mean removal.

Obliterate means to destroy completely; obviate means to prevent the need for.

The bomb obliterated the building. The new design obviated the need to demolish the building.

obvidable vs abbreviate

Phonetic ending '-iate'.

Abbreviate means to shorten; obviate means to prevent.

We abbreviate 'Doctor' to 'Dr.'. We obviate the need for titles in our casual office.

obvidable vs deviate

Phonetic ending '-iate' and shared 'via' root.

Deviate means to turn away from a path; obviate means to remove a path's necessity.

Do not deviate from the plan. The new plan obviates the old path.

Sentence Patterns

Subject + will obviate the need for + Noun.

The new app will obviate the need for paper tickets.

Subject + obviates the necessity of + Gerund.

The agreement obviates the necessity of hiring more staff.

Subject + is designed to obviate + Abstract Noun.

The policy is designed to obviate systemic bias.

By + Gerund, Subject + obviates + Noun.

By automating the process, the company obviates human error.

Subject + obviates the possibility of + Noun.

The sheer scale obviates the possibility of failure.

It is hoped that + Subject + will obviate + Noun.

It is hoped that the new treaty will obviate further conflict.

Noun + having been obviated, + Clause.

The need for a trial having been obviated, the parties went home.

Subject + seeks to obviate + Complex Noun Phrase.

The theory seeks to obviate the traditional dichotomy.

Word Family

Nouns

obviation (the act of obviating)

Verbs

obviate

Adjectives

obviable (capable of being obviated)

obvious

obviating

obviated

via

viaduct

How to Use It

frequency

Low in general speech, high in specific professional literature.

Common Mistakes

Using 'obviate' to mean 'to make clear'. → The evidence obviates the need for a trial.
People confuse it with 'obvious'. It means to prevent, not to clarify.
Using 'obviate' with a person as the object. → The robot obviates the need for a cleaner.
You don't obviate the cleaner; you obviate the *need* for one.
Saying 'obviate for'. → This will obviate the need.
Obviate is transitive; it doesn't take the preposition 'for' directly.
Confusing 'obviate' with 'obliviate'. → The update obviates the bug.
Obliviate means to forget (or is a fictional spell); obviate means to prevent.
Using 'obviate' for a simple 'stop'. → The wall prevented the water from entering.
Obviate is for removing a *requirement* or *necessity*, not just physical stopping.

Tips

Use with 'Need'

Whenever you aren't sure how to use 'obviate', just pair it with 'the need for'. It works 90% of the time.

Academic Writing

Use 'obviate' in your thesis to describe how your research makes previous complex models unnecessary.

Business Efficiency

In meetings, use 'obviate' to describe how a new strategy will save time and money by removing steps.

Check the Object

Ensure the object of 'obviate' is an abstract noun like 'necessity', 'risk', or 'expense'.

The 'Ob-Via' Connection

Remember that 'via' means way. Obviate is getting 'in the way' of a problem before it starts.

Avoid Redundancy

Don't say 'obviate the unnecessary need'. 'Obviate' already implies the need is gone.

Stress the Start

Say it like 'OB-vee-ate'. Don't let the 'vi' part get too long.

Obviate vs Alleviate

Remember: Alleviate = make better; Obviate = make unnecessary.

Preclude vs Obviate

Use 'preclude' for things that are blocked; use 'obviate' for things that are no longer needed.

Global English

This word is understood by educated speakers globally, especially in law and science.

Memorize It

Mnemonic

OBVIATE = OBVIOUSLY ELIMINATE. If you obviate something, you obviously eliminate the need for it.

Visual Association

Imagine a giant 'X' being placed over a 'To-Do' list item before you even start your day. That 'X' is the action that obviated the task.

Word Web

Prevent Remove Strategy Efficiency Necessity Innovation Preclude Foresight

Challenge

Try to identify one task in your daily routine that could be obviated by a simple change in your habits.

Word Origin

From the Latin 'obviare', which means 'to meet' or 'to withstand'. It is composed of 'ob' (against/in the way) and 'via' (way).

Original meaning: To meet someone on the road, or to encounter and withstand an opponent.

Indo-European (Latin branch)

Cultural Context

No specific sensitivities, but avoid using it in casual conversation as it can sound pompous or 'trying too hard'.

Highly formal; used in 'The Economist', 'The New York Times', and academic journals.

Often used in Supreme Court opinions to describe how one law affects another. Found in technical documentation for companies like Apple or Microsoft regarding system updates. Used in philosophical texts to discuss the removal of logical necessities.

Practice in Real Life

Real-World Contexts

Business strategy

obviate the need for layoffs
obviate redundant processes
obviate market risks
obviate middleman costs

Legal drafting

obviate further litigation
obviate the necessity of a trial
obviate contractual disputes
obviate regulatory hurdles

Medical research

obviate the need for surgery
obviate invasive testing
obviate side effects
obviate chronic symptoms

Engineering

obviate structural failure
obviate manual overrides
obviate the need for cooling
obviate friction

Daily life

obviate the need to cook
obviate a long commute
obviate a difficult conversation
obviate the cost of parking

Conversation Starters

"Do you think AI will eventually obviate the need for people to learn coding?"

"What's one modern invention that has completely obviated a task you used to hate?"

"Could a universal basic income obviate the need for traditional welfare systems?"

"Does having a smartphone obviate the need for a dedicated camera for most people?"

"How can we design our cities to obviate the need for private car ownership?"

Journal Prompts

Reflect on a time when a proactive decision you made obviated a major problem later on.

Identify three tasks in your professional life that you wish could be obviated by technology.

Discuss whether digital communication obviates the need for face-to-face social interaction.

Write about a theoretical product that would obviate the need for sleep. What would the consequences be?

How does the concept of 'obviating' apply to your personal philosophy of problem-solving?

Frequently Asked Questions

10 questions

No, you cannot 'obviate' a human being. You can only 'obviate' a requirement, a need, or a difficulty associated with them. For example, 'The new system obviates the need for a secretary,' not 'The new system obviates the secretary.'

The word is actually 'obviable', meaning capable of being obviated. However, 'obviate' (the verb) is much more common. 'Obvidable' is likely a misspelling of 'obviable' or 'obviate'.

The most common way is: [Something new] obviates the need for [something old/difficult]. Example: 'Digital cameras obviate the need for film.'

Both are correct, but 'obviate the need' is the most natural-sounding collocation in modern English. You can also say 'obviate the risk' or 'obviate the difficulty'.

The most direct opposite is 'necessitate', which means to make something necessary. If a flat tire obviates your drive, a long distance necessitates a car.

In a professional business email to a client or boss, it is appropriate. In an email to a friend, it might sound a bit stiff or funny.

Prevent is general (I prevented the fire). Obviate is about making something redundant (The fireproof material obviated the need for a sprinkler system).

No, 'obviate' already implies the 'away' part. It is a self-contained verb of removal.

Yes, 'obviation', though it is very rare. You'll almost always see the verb form.

It comes from the Latin 'obviare', meaning to meet in the way. It's related to 'via' (way/road).