Translation guide
A guide to expressing the concept of sexual intercourse in Japanese, from clinical terms to everyday euphemisms, with notes on register and natural usage.
The most standard, widely understood word for sexual intercourse, suitable for formal, medical, or neutral contexts.
The standard clinical/formal term for sexual intercourse. Used in medical, legal, and educational contexts. Not typically used in casual conversation.
性交は生殖の手段の一つです。
Sexual intercourse is one means of reproduction.
The most common everyday word for sex. Borrowed from English, used in casual and informal contexts. Can refer to the act or to sexual activity in general.
Softer, indirect ways to refer to sexual intercourse, often used in polite conversation, media, or when avoiding explicit language.
Very casual, often crude words for sexual intercourse. Use with caution; these can be offensive.
From the letter 'H', a very common slang term for sex or sexual activity. Can be used as a noun or a verb (エッチする). Milder than English 'fuck', but still informal.
Precise terms used in law, medicine, or academic writing.
Expressions specifically for having sex for the first time.
Japanese has a wide gap between clinical terms like 性交 and slang like エッチ. Using 性交 in casual conversation sounds stiff and unnatural, while using ヤる in polite company is offensive. セックス is the safest everyday word, but still direct. When in doubt, use euphemisms like 肉体関係 or 体の関係 for sensitive topics.
性交 is clinical/formal, セックス is neutral/casual, and エッチ is slangy but not as vulgar as English 'fuck'. エッチ can also be used as an adjective meaning 'lewd' or 'perverted', so context is key.
彼氏とセックスした。
I had sex with my boyfriend.
Literally 'physical relationship'. A common euphemism for a sexual relationship, often used in news, gossip, or formal discussion about affairs.
二人は肉体関係を持っていた。
The two had a physical relationship.
Literally 'sexual relationship'. Similar to 肉体関係 but slightly more explicit. Used in formal or legal contexts.
性的関係を持つことは同意が必要です。
Consent is necessary for having sexual relations.
A softer, more colloquial euphemism than 肉体関係. Often used in personal conversations or drama dialogue.
彼とは体の関係だけだ。
I just have a physical relationship with him.
昨日、彼女とエッチした。
I had sex with my girlfriend yesterday.
A vulgar slang verb meaning 'to do' someone, i.e., to have sex. Often used by men. Crude and should be avoided in polite company.
Very crude; equivalent to 'bang' or 'screw'. Not appropriate in formal or mixed company.
あの女とヤりたい。
I want to bang that chick.
A formal term for sexual act or sexual conduct. Broader than 性交, can include non-penetrative acts. Common in legal and educational contexts.
同意のない性行為は犯罪です。
Non-consensual sexual acts are a crime.
A biological term for copulation, used mainly in zoology or very technical medical contexts. Not used in everyday language.
動物の交接行動を観察した。
We observed the copulation behavior of the animals.
Literally 'first experience', commonly used to mean losing one's virginity. Can be used for other first experiences, but context usually makes it clear.
初体験はいつですか？
When was your first time?
A straightforward phrase meaning 'first sex'. Clear and unambiguous.
初めてのセックスは緊張する。
The first time you have sex, you get nervous.
エッチする
to have sex (slang)