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 spouse or partner
b
: unfaithfulness to a moral obligation : disloyalty
infidelity to the group's guiding principles
2
: lack of belief in a religion
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
Factors in the split included Bill’s links to Epstein and his infidelity.
—
Rachel Burchfield, InStyle, 5 Feb. 2026
Singer Billie Eilish — one of Wasserman’s clients at his entertainment agency — stepped away from his firm because of the infidelity allegations, according to the Hollywood Reporter.
—Dakota Smith, Los Angeles Times, 5 Feb. 2026
In December, Kristy alleged infidelity as the reason for her split from Desmond, per court records previously obtained by PEOPLE.
—Zoey Lyttle, PEOPLE, 29 Jan. 2026
One couple will discover infidelity.
—Marta Balaga, Variety, 29 Jan. 2026
See All Example Sentences for infidelity
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Rachel Burchfield, InStyle, 5 Feb. 2026
Singer Billie Eilish — one of Wasserman’s clients at his entertainment agency — stepped away from his firm because of the infidelity allegations, according to the Hollywood Reporter.
—Dakota Smith, Los Angeles Times, 5 Feb. 2026
In December, Kristy alleged infidelity as the reason for her split from Desmond, per court records previously obtained by PEOPLE.
—Zoey Lyttle, PEOPLE, 29 Jan. 2026
One couple will discover infidelity.
—Marta Balaga, Variety, 29 Jan. 2026
See All Example Sentences for infidelity
Cite this Entry
“Infidelity.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/infidelity. Accessed 15 Feb. 2026.
Copy CitationKids 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
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