双生児|そうせいじsouseiji[3]nakadaka (mid-high)

1. nountwins
   肉体にくたいと精神せいしんとは双生児そうせいじであり、神かみのみがどちらがどちらなのかを知しっている。↗

   Body and spirit are twins: God only knows which is which.

• Synonym双子ふたごNeutralThe everyday word for twins and by far the commoner choice; 「双生児」 sounds medical and written, as in 「一卵性双生児」.
• Related双生子WrittenA written word for twins, but rarely used; say 「双子」 or 「双生児」 instead.

In everyday speech say 「双子」, which can also describe things strikingly alike. 「双生児」 is the formal, medical and statistical term, as in 「一卵性双生児」. 「双生子」 is a rare written variant.

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

1. 多胎児たたいじに含ふくまない双子ふたごの言い方いいかた。^([要よう出典しゅってん])