infidelity
noun/ˌɪnfɪˈdɛlɪti/
Etymology From Middle English infidelite, from Middle French infidelité (modern French infidélité) and its etymon Latin īnfidēlitās. Equivalent to infidel + -ity.
1
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.
- Your friends tell you rumors about your girlfriend's infidelity or you remember being broken up around the time the baby was conceived.2013, William G. Staples, Everyday Surveillance: Vigilance and Visibility, →ISBN, page 155:
2
Unfaithfulness in some other moral obligation.
- It was disastrous that England's infidelity towards Frederick the Great — which no one, not even a German, condemned more strongly than did William Pitt — had to affect one of the most popular heroes of our national history.1937, Arnold Oskar Meyer, England in German opinion throughout the centuries, page 6:
3
Archaic Lack of religious belief.
- The means used to this purpose are partly didactical, and partly protreptical; demonstrating the truth of the gospel, and then urging the professors of those truths to be stedfast^([sic]) in the faith, and to beware of infidelity.1674, Seth Ward, Seven Sermons:
- The Churchman remarked that such incidents arose from the growing infidelity, while the Freethinker saw in them a reversion to superstition.1926, Arthur Conan Doyle, The Land of Mist:
- Synonyms
- Synonyms: adultery, betrayal, faithlessness
- Antonyms
- faithfulness, loyalty, fidelity
- Related terms
- infidel, low fidelity, nullifidianism, unfaithfulness