infidelity

noun

in·​fi·​del·​i·​ty ˌin-fə-ˈde-lə-tē 

-(ˌ)fī-

plural infidelities

1

a

: the act or fact of having a romantic or sexual relationship with someone other than one's husband, wife, or partner

b

: unfaithfulness to a moral obligation : disloyalty

2

: lack of belief in a religion

Synonyms

• disloyalty
• faithlessness
• falseness
• falsity
• inconstancy
• perfidiousness
• perfidy
• unfaithfulness

Examples of infidelity in a Sentence

She was convinced that her husband was guilty of infidelity.

He has admitted to a number of marital infidelities.

Recent Examples on the Web

Then came all the reports of infidelity, so much his reputation as a legendary winner shattered as if somebody had taken a golf club to it. —Mike Lupica, New York Daily News, 20 July 2024

Sometimes, a relationship can detonate in spectacles of pure id—ravenous infidelity, screaming arguments, sobbing in bar bathrooms, 200 texts per hour—eventually leaving both ends of the partnership feeling raw, extreme, and ideally, free. —Carolyn Wells, Longreads, 5 July 2024

Unplanned pregnancies, infidelities, theft, drug feuds (money owed, territories infringed upon), Chinese whispers, blatant lies, betrayal, violence, crime, shady exchanges, and the list goes on. —Brandi California, SPIN, 1 July 2024

Though it’s not noted in the song itself, Rivera dealt with domestic abuse, infidelity, divorce and more in her personal life. —Andrea Flores, Los Angeles Times, 26 June 2024

Word History

Etymology

Middle English infidelite, borrowed from Middle French infidelité, borrowed from Latin infidēlitāt-, infidēlitās "faithlessness, inconstancy," from infidēlis "unfaithful, disloyal" + -itāt-, -itās -ity — more at infidel entry 2

First Known Use

15th century, in the meaning defined at sense 2

Kids Definition

infidelity

noun

in·​fi·​del·​i·​ty ˌin-fə-ˈdel-ət-ē 

-(ˌ)fī-

plural infidelities

1

: lack of faith in a religion

2

: unfaithfulness especially to one's husband or wife