Translation guide
The English word "sex" has two main meanings: biological sex (male/female) and sexual activity. These are expressed with different words in Japanese. This guide helps learners choose the right term based on context.
Referring to whether a person or animal is male or female, often in formal or medical contexts.
The standard, neutral word for 'sex' as a category (male/female). Used in forms, surveys, and everyday conversation.
性別を教えてください。
Please tell me your sex.
この書類には性別を記入する欄があります。
There is a field to fill in your sex on this form.
Often used in compounds or formal contexts, such as 'same-sex' or 'sex discrimination'. Can sound technical alone.
性による差別は許されません。
Discrimination based on sex is not permitted.
Literally 'male and female', used to refer to sex in a binary sense, often in phrases like '男女平等' (gender equality).
男女の区別なく採用します。
We hire regardless of sex.
Referring to the act of sex, sexual intercourse, or sexual relations.
The most common and direct loanword for 'sex' as an activity. Used in casual and formal contexts, but can be blunt.
彼らはセックスについてオープンに話す。
They talk openly about sex.
セックスは愛情表現の一つです。
Sex is one way of expressing love.
Formal or clinical term for 'sexual intercourse'. Used in legal, medical, or educational contexts.
Technical/medical term for 'sexual intercourse'. Rare in everyday speech.
Casual, euphemistic way to say 'have sex'. Common in informal conversation. Can be used as a verb (する) or noun (エッチ).
昨日彼とエッチした。
I had sex with my boyfriend yesterday.
Literally 'have a physical relationship', a euphemism for having sex. Somewhat formal or indirect.
彼女とは体の関係を持っていません。
I don't have a sexual relationship with her.
Referring to sex education, discussions about sex, or the concept of sexuality.
Sex education. Use this when talking about teaching about sex.
学校で性教育を受けた。
I received sex education at school.
Can mean 'sexuality' or 'sex' as a broad concept. Often used in compounds like 性の問題 (sexual issues).
性について話すのは難しい。
It's difficult to talk about sex.
性別 (seibetsu) means biological sex (male/female). セックス (sekkusu) means sexual activity. Using セックス on a form to ask for someone's sex would be inappropriate and confusing.
性別：男・女
Sex: Male/Female
セックス is the most common and neutral in everyday speech. 性行為 is formal and used in official contexts. 性交 is technical/medical and rarely used in conversation.
性行為感染症に注意してください。
Be careful of sexually transmitted infections.
性交渉を持つ前に同意を確認することが大切です。
It's important to confirm consent before having sexual intercourse.