How to say "swear" in Japanese

• 誓うちかうJLPT N2approx.Common
  godan verb, transitive verbCovers 'swear' in the sense of making a solemn vow or oath — promising to do something or swearing that something is true. The usual choice, e.g. vowing never to make the same mistake twice.
  君きみは聖書せいしょに手てをのせて誓ちかうべきだ。↗

  You should swear on the Bible.
• 契るちぎるJLPT N1approx.
  godan verbAlso covers 'swear' as a solemn vow, but it is less common and seldom the word you want in ordinary speech; its flavor is weighty and binding, as in vows made before the gods.

Both translate 'swear' as a solemn vow or oath — choose 「誓う」 for ordinary solemn promises, while 「契る」 is a less common alternative with a weighty, binding flavor; neither covers swearing in the sense of using profanity.

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

• 誓うちかうto swear
• 契るちぎるto pledge
• 固めるかためるto swear