性交|せいこうseikou[0]heiban (flat)

Common
Definitions
  1. noun, suru verb, intransitive verbsexual intercourse; sex; coitus
    性交せいこうの最中さいちゅう彼女かのじょはつまらなそうな顔かおをしていた。↗
    She looked bored while we were making love.
Conjugation
Dictionary form性交する(せいこうする)
Polite (masu)性交します(せいこうします)
Negative (nai)性交しない(せいこうしない)
polite (masen)性交しません(せいこうしません)
classical zu / nu性交せず・性交せぬ(せいこうせず・せいこうせぬ)
Past (ta)性交した(せいこうした)
polite (mashita)性交しました(せいこうしました)
Past negative (nakatta)性交しなかった(せいこうしなかった)
polite (masen deshita)性交しませんでした(せいこうしませんでした)
Te form性交して(せいこうして)
Potential性交できる(せいこうできる)
Passive性交される(せいこうされる)
Causative性交させる(せいこうさせる)
Causative passive性交させられる(せいこうさせられる)
Conditional (ba)性交すれば(せいこうすれば)
tara性交したら(せいこうしたら)
Volitional性交しよう(せいこうしよう)
polite (mashou)性交しましょう(せいこうしましょう)
Imperative性交しろ(せいこうしろ)

Common forms generated by rule; see the senses for honorific or irregular usage.

Synonyms & antonyms
  • SynonymセックスNeutralA loanword and the direct, colloquial way to say it; also means gender. 「性交」 is the formal written term used in medicine and law.
  • Synonym性行為せいこういWrittenWritten term for sexual activity, typical of medicine, education and news reporting; close to 「性交」 but somewhat more euphemistic.
  • Related営みいとなみWrittenWritten and euphemistic: 「夜の営み」 means a couple's sex life. Its basic sense is work or activity.
  • Related交合こうごうWrittenWritten word for sexual union, leaning classical or biological; rarely used.
  • Related交接こうせつWrittenWritten word for mating or copulation, mainly in biology; can also mean interaction or association.
  • Related情交じょうこうWrittenWritten word for an intimate liaison between a man and a woman; literary in flavor.

Use 「性交」 or 「性行為」 in formal medical or legal contexts, 「セックス」 in everyday speech, and 「夜の営み」 as a euphemism; for animal mating, 「交尾」 is the word.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

Japanese definitions
  1. 生殖せいしょくや快楽かいらくのために主おもに性器せいきを介かいして交まじわること。
Kanji in this word
English equivalents

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