Definition of infidelity
1 : lack of belief in a religion
2a : unfaithfulness to a moral obligation : disloyaltyb : the act or fact of having a romantic or sexual relationship with someone other than one's husband, wife, or partner
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.
First Known Use of infidelity
Seen and Heard
What made you want to look up infidelity? Please tell us where you read or heard it (including the quote, if possible).