Translation guide
The English phrase "sexual relations" is a formal or euphemistic term for sexual activity. In Japanese, the most natural equivalent depends heavily on context, register, and the relationship between speakers. Direct translations can sound clinical, legal, or awkward. This guide covers common expressions from formal to casual, including euphemisms and slang.
To refer to sexual activity in a formal, legal, or medical setting, such as in court documents, medical reports, or official statements.
The most direct formal equivalent. Used in legal, medical, and official contexts. It is neutral and clinical.
彼らは性交渉を持ったと証言した。
They testified that they had sexual relations.
To talk about sexual activity without being overly explicit, in a way that is polite but not clinical. Suitable for general conversation or media.
Literally 'physical relationship'. A common euphemism used in news, gossip, and everyday talk. Implies a sexual relationship, often outside of marriage or in a scandal context.
二人は肉体関係にあったと言われている。
It is said that the two had sexual relations.
Literally 'man-woman relationship'. A softer euphemism, often used to imply a romantic/sexual relationship without stating it directly. Common in dramas and novels.
彼らは男女の関係になった。
They became involved in a sexual relationship.
Literally 'deep relationship'. A vague euphemism that can mean a close emotional bond, but in context implies a sexual one. Use with caution as it can be ambiguous.
彼女とは深い関係になった。
I got into a deep (sexual) relationship with her.
To talk about having sex in everyday conversation with friends or in informal settings.
The most common and direct way to say 'have sex'. A loanword from English, used casually. Can be used in questions and statements.
昨日、彼とセックスした。
I had sex with my boyfriend yesterday.
Slang for 'have sex', derived from the letter 'H' (from 'hentai'). Softer and more playful than セックスする. Often used by younger people or in light conversation.
付き合って三ヶ月で初めてエッチした。
We had sex for the first time after dating for three months.
A very crude slang term for 'have sex', equivalent to 'do it' or 'bang'. Can be vulgar and is typically used among close male friends. Avoid in polite company.
Very informal and can be offensive. Use only with close friends.
To allude to sexual activity without naming it, often in polite or ambiguous contexts.
Literally 'to have a relationship'. In context, it often means a sexual relationship. It is a common euphemism in news and formal speech.
彼は複数の女性と関係を持っていた。
He had sexual relations with multiple women.
Literally 'to cross the line'. An idiomatic expression meaning to go from a platonic to a sexual relationship. Often used in dramas and novels.
二人はついに一線を越えた。
The two finally crossed the line (had sex).
The direct translation '性的関係' (seiteki kankei) is understood but can sound unnatural or overly clinical in everyday speech. It is mainly used in formal contexts like law or academia. For most situations, choose a euphemism like 肉体関係 or a casual term like セックスする.
性的関係を持ったことがありますか？
Have you ever had sexual relations? (sounds like a medical questionnaire)
Both are euphemisms, but 肉体関係 emphasizes the physical aspect and is often used in scandalous or gossipy contexts. 男女の関係 is softer and can imply a romantic relationship that includes sex. In many cases they are interchangeable, but 肉体関係 is more direct about the sexual nature.
セックスする is a suru-verb and conjugates normally. It is casual but not vulgar. You can use it with friends or in dating contexts. To make it more polite, you can use セックスをする or add ます (セックスします), but it may still sound direct. For very polite situations, use a euphemism.
その政治家はスタッフと肉体関係を持ったことを認めた。
The politician admitted to having sexual relations with a staff member.
Uses 肉体関係, a common euphemism in news.
契約書は従業員間の性交渉を禁止している。
The contract prohibits sexual relations between employees.
Formal/legal context, uses 性交渉.
Also formal, but slightly broader, can include non-physical sexual interactions. Often used in discussions of harassment or ethics.
上司と部下の性的関係は問題だ。
Sexual relations between a boss and subordinate are problematic.
I heard those two did it yesterday.