infidelity
in-fih-DEL-ih-tee
/ˌɪnfɪˈdeləti/
The action or state of being unfaithful to a spouse or other sexual partner.
A broad, often clinical or formal term that covers both emotional and physical breaches of trust in a committed relationship.
The story behind the word. From the Latin 'infidelitas,' originally referring to a lack of religious faith. By the late 14th century, it evolved to describe a breach of the marriage vow, mirroring the idea of 'breaking faith' with a partner.
Word relationships
- unfaithfulness: A more common, less clinical term for the same concept.
- cheating: Informal and carries a stronger emotional or judgmental weight.
- fidelity: The state of being loyal and faithful.
- faithfulness: The quality of staying true to a partner.
Commonly confused with
- adultery: Adultery is specifically a legal and religious term for sex between a married person and someone not their spouse; infidelity is broader.
Word family
- infidelities (noun): Plural instances of being unfaithful.
Collocations
- marital infidelity
- suspected infidelity
- confess to infidelity
Example sentences
- "Infidelity is often cited as one of the primary reasons for the dissolution of long-term marriages." A psychological study on relationships.
- "The discovery of his infidelity was a blow from which their domestic peace never recovered." Classic literature discussing the nature of trust.
Memory hook
Think of 'in-' (not) and 'fidelity' (loyalty). If you have infidelity, you have NO loyalty. No faith, no fidelity.
When not to use
Avoid using it for minor broken promises; it almost exclusively refers to romantic or sexual cheating.
Fun facts
- In the Middle Ages, 'infidel' was a term for someone of a different religion; the romantic meaning came later.
Related words
Explore more words
fidelity, treachery, Breach, perfidious, desertion, misconduct
Also appears in
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