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Added 9 October 2026

infidelity

/ˌɪnfɪˈdɛlɪti/ noun

Latin root: īnfidēlitās Wiktionary

noun Definition from Wiktionary (CC BY-SA). Pronunciation from Wiktionary, via Kaikki.org. More about infidelity at Wordnik → Where our words come from →

Unfaithfulness in a marriage or an intimate (sexual or romantic) relationship: practice or instance of having a sexual or romantic affair with someone other than one's spouse, without the consent of the spouse.
Unfaithfulness in some other moral obligation.
Lack of religious belief.

Origin

From Middle English infidelite, from Middle French infidelité (modern French infidélité) and its etymon Latin īnfidēlitās. Equivalent to infidel + -ity.

From Wiktionary, via Kaikki.org (CC BY-SA)

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