入院する

The Japanese verb 入院する (nyuuin suru) is a quintessential 'suru-verb' that translates directly to 'to be hospitalized' or 'to enter the hospital for treatment.' At its linguistic core, the word is composed of two kanji characters: 入 (nyuu), meaning 'to enter' or 'to put in,' and 院 (in), which refers to an institution, specifically a hospital (byouin) in this context. Unlike a simple visit to the doctor for a check-up or a cold, 入院する implies a stay that lasts at least overnight. In the Japanese medical system, hospitalization is often handled with a high degree of formality and specific social protocols, such as the tradition of omimai (visiting the sick with gifts).

Core Concept

The act of being admitted to a medical facility for inpatient care, involving an overnight stay or longer duration.

Grammatical Category

A compound noun (入院) combined with the irregular verb する (suru), making it a Class 3 or 'Suru' verb.

Cultural Nuance

Hospitalization in Japan can sometimes be longer than in Western countries, as hospitals often provide recovery care that might be done at home elsewhere.

You will encounter this word in a variety of settings, ranging from daily conversations among family members to formal news broadcasts discussing public figures. For instance, if a celebrity is exhausted, the news might report they have 入院した for 'rest and recuperation.' In a workplace, if a colleague is absent for an extended period, the HR department might use this term to explain the medical leave. It is a neutral, factual term that carries the weight of a serious medical situation without being overly graphic or alarmist. It covers everything from minor surgery to long-term chronic care.

The word is also used in compound forms. For example, nyuuin-seikatsu (hospital life) refers to the daily routine one follows while admitted. Understanding 入院する is vital for navigating health-related discussions in Japan, as it distinguishes between a simple outpatient visit (tsuuin) and the more serious commitment of staying at the facility. It is also important to note that the particle used for the destination is almost always に (ni), indicating the point of entry into the institution.

Using 入院する (nyuuin suru) correctly requires a firm grasp of Japanese particle usage and verb aspects. The most common sentence structure is: [Subject] は [Hospital/Location] に 入院する. The particle に (ni) is crucial here because it marks the target or destination of the 'entering' action. While you might be tempted to use で (de) to describe where the action of staying happens, 入院する describes the transition into the state of being an inpatient, hence に is the standard choice.

The 'Te-iru' Form

Use nyuuin shite iru to describe the ongoing state of being in the hospital. This is the most common way to say 'He is in the hospital' in English.

The 'Koto ni naru' Pattern

Often used as nyuuin suru koto ni natta (It has been decided that [I/they] will be hospitalized), which sounds more natural and objective in medical contexts.

Duration Markers

When specifying how long, use [Time Period] + kan. For example, isshuukan nyuuin suru (to be hospitalized for one week).

In formal Japanese, particularly in medical reports or when speaking to superiors, you might use the humble or polite versions of the verb. However, for most A2-B1 learners, the standard 入院します (nyuuin shimasu) is perfectly appropriate. Another important aspect is the reason for hospitalization, which is often indicated with the particle で (de) meaning 'due to' or 'by means of.' For example, kensa de nyuuin suru (hospitalized for/by way of testing).

When discussing the end of a hospital stay, you switch to the antonym 退院する (taiin suru). It is common to see these two used together in progress updates: Nyuuin shite kara, itsu taiin dekimasu ka? (After being hospitalized, when can I be discharged?). Note that the verb doesn't take a direct object with を (wo) because you aren't 'hospitalizing' the hospital; you are 'performing the act of hospitalization' upon yourself or someone else is the subject.

The word 入院する (nyuuin suru) is ubiquitous in Japanese society due to the country's comprehensive health insurance system and aging population. You will hear it most frequently in the following contexts: 1) Medical facilities during consultations, 2) News reports about public figures, 3) Daily conversations about family and friends, and 4) Workplaces when discussing leaves of absence. In Japan, the threshold for 入院 can sometimes be lower than in the US or UK; for instance, someone might be hospitalized for a few days just to undergo a series of comprehensive tests called a 'ningen dock' if complications are suspected.

TV News & Media

Commonly used when a politician or celebrity takes a break. Phrases like 'kensa nyuuin' (hospitalization for testing) are very common.

Workplace Announcements

Colleagues might say, 'Tanaka-san wa nyuuin chuu desu' (Mr. Tanaka is currently hospitalized) to explain his absence.

Hospitals & Clinics

Doctors use it to recommend treatment: 'Nyuuin shite chiryou shimashou' (Let's hospitalize you and begin treatment).

In anime and drama, 入院する is a common plot device. It often signals a turning point in a character's arc or a moment of high emotional stakes. You might hear a character crying out, 'Nande nyuuin nante koto ni...!' (How did it come to hospitalization...!). It's also part of the specialized vocabulary for 'hospital dramas' (iryou dorama), which are a staple of Japanese television. In these shows, the process of nyuuin involves paperwork, consent forms (douisho), and the assignment of a room (byoushitsu).

Even in casual settings, Japanese people are quite open about mentioning 入院. It isn't necessarily a taboo subject, although the specific details of the illness might be kept private. If you are visiting a friend in the hospital, you would use this word to describe their current state. You might also see signs in hospitals like 'Nyuuin Uketsuke' (Hospitalization Reception) or 'Nyuuin Annai' (Information for Inpatients). These are practical places where the word becomes part of the physical landscape.

One of the most frequent errors English speakers make with 入院する (nyuuin suru) is confusing it with simply 'going to the hospital.' In English, 'I went to the hospital' can mean you went for a 15-minute appointment or you were admitted for surgery. In Japanese, byouin ni iku (going to the hospital) is used for outpatient visits, while 入院する is strictly for staying there. Another common mistake involves the misuse of particles, specifically using を (wo) instead of に (ni).

Mistake: Particle Confusion

Saying Byouin wo nyuuin suru is incorrect. The hospital is the destination, not the object of the verb. Always use Byouin ni nyuuin suru.

Mistake: Overusing 'Suru'

Saying nyuuin shita when you mean the person is still there. Use nyuuin shite iru for the current state.

Mistake: Confusing with 'Nyuugaku'

Because both start with 'nyuu' (enter), beginners sometimes mix up 入院 (hospital) and 入学 (schoo