不ふ貞てい

noun, na-adjective, noun which may take the genitive case particle 'no'

unfaithfulness; infidelity; unchastity

Refers to sexual unfaithfulness in a committed relationship, especially marital infidelity. Often used in formal or literary contexts.

• 彼かれの不ふ貞ていが原げん因いんで離り婚こんした。

  They divorced because of his infidelity.

• 不ふ貞ていな行こう為いは許ゆるされない。

  Unfaithful acts are unforgivable.