infidelity
ihn-fih-DEH-lih-tee
/ˌɪnfɪˈdeləti/
The action or state of being unfaithful to a spouse or romantic partner; unfaithfulness to a moral obligation.
Most commonly used in romantic contexts to describe cheating, but can also describe a breach of faith to a religion or cause.
The story behind the word. Infidelity comes from the Latin 'infidelitas', from 'infidelis' (unfaithful). This is built from 'in-' (not) and 'fidelis' (faithful), which traces back to 'fides' (faith). Historically, it was used to describe those who did not hold the same religious faith.
Word relationships
- unfaithfulness: Unfaithfulness is a simpler, more direct term, while infidelity sounds more clinical or formal.
- fidelity: Fidelity is faithfulness to a person, cause, or belief, demonstrated by continuing loyalty and support.
Commonly confused with
- infinity: Infinity refers to boundless time or space, while infidelity refers to unfaithfulness.
Word family
- infidel (noun): A person who does not believe in religion or adheres to a religion other than one's own.
Collocations
- marital infidelity
- accused of infidelity
- discover infidelity
Idioms & expressions
- cheat on
- stray from the path
Example sentences
- "The couple attempted marriage counseling, but the pain of his emotional infidelity proved too difficult to overcome." A discussion on the breakdown of a relationship.
Memory hook
Think of the Marine Corps motto 'Semper Fidelis' (Always Faithful). 'Infidelity' is the exact opposite—never faithful. The opposite of Semper Fi.
When not to use
Do not use to describe a simple business disagreement; it must involve a breach of a solemn personal or spiritual commitment.
Fun facts
- In medieval Europe, an 'infidel' was not just a romantic cheater, but a term of heavy political and religious condemnation for anyone outside the dominant church.
Explore more words
fidelity, treachery, Breach, perfidious, desertion, misconduct
Also appears in
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