Translation guide
This entry covers how to express the concept of having sexual intercourse in Japanese, ranging from formal and medical terms to casual and slang expressions. The focus is on natural usage for an English-speaking learner.
They had sexual intercourse.
Common loanword from English 'sex'. Widely understood and used in casual to semi-formal speech. More colloquial than 性交する.
I had sex with my girlfriend yesterday.
Literally 'to have a physical relationship'. A euphemistic and somewhat formal way to refer to sexual intercourse, often used in serious discussions or writing.
They had a physical relationship.
To express 'have sexual intercourse' in very casual or slangy ways, often among friends or in informal settings.
A versatile slang verb meaning 'to do' or 'to have sex'. Very casual and can be crude. Context makes the meaning clear.
Can sound vulgar or objectifying if used inappropriately. Avoid in polite conversation.
Did you do it yesterday?
Literally 'to sleep', but euphemistically means 'to have sex' when context implies sharing a bed. Common in casual speech.
From the letter 'H' (ecchi), meaning 'perverted' or 'sex'. A common, slightly childish or playful way to say 'have sex'. Used among young people.
I had sex with my boyfriend.
Onomatopoeic slang for the sound of sex, used as a verb. Very crude and vulgar, often used in online or male-oriented banter.
Extremely vulgar. Only use with close friends who understand the crudeness, if at all.
I wanna bang that girl.
To refer to sexual intercourse in strictly formal, medical, or legal contexts.
A formal term meaning 'to have sexual relations'. Used in legal, medical, or official documents.
The defendant had sexual intercourse with the victim.
Biological term for copulation, used for animals or in clinical descriptions of human intercourse. Very technical.
This species copulates in spring.
To allude to having sexual intercourse without being explicit, often in polite or sensitive conversations.
Literally 'to have a relationship', but context implies sexual relationship. Softer than 肉体関係を持つ.
I ended up having a relationship (sexual) with him.
Idiom meaning 'to cross the line', implying moving from a platonic to a sexual relationship. Used in dramatic or narrative contexts.
The two finally crossed the line (had sex).
Poetic expression meaning 'to lay bodies on top of each other', a euphemism for sex. Found in novels or songs.
The two in love lay together (had sex).
While セックスする is a common loanword, directly translating 'have sexual intercourse' as 性交する can sound overly clinical in casual conversation. Choose the term based on context and relationship.
You wouldn't normally ask a friend 'Did you have sexual intercourse yesterday?'
やる is the most crude and direct, often used by males. 寝る is a softer euphemism focusing on the act of sleeping together. エッチする is playful and common among younger people, but can sound childish. Choose based on the nuance you want to convey.
He said 'I did it' but she said 'I slept with him'.
I slept with him.