unfaithful

American  

[uhn-feyth-fuhl] / ʌnˈfeɪθ fəl /

adjective

1. not faithful; false to duty, obligation, or promises; disloyal.

   Given how unfaithful the party has been to voters, it would be surprising if they won.

   Synonyms:

   recreant, treacherous, deceitful, untrustworthy

2. not sexually loyal to a spouse or lover; adulterous.

   She was concerned her husband would be unfaithful when he travelled.

3. not accurate or complete; inexact.

   The book was an unfaithful translation of the original.

   Synonyms:

   untrue, imprecise

4. Obsolete. without religious faith; unbelieving.

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unfaithful British  

/ ʌnˈfeɪθfʊl /

adjective

1. not true to a promise, vow, etc

2. not true to a wife, husband, lover, etc, esp in having sexual intercourse with someone else

3. inaccurate; inexact; unreliable; untrustworthy

   unfaithful copy

4. obsolete not having religious faith; infidel

5. obsolete not upright; dishonest

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Other Word Forms

• unfaithfully adverb
• unfaithfulness noun

Etymology

Origin of unfaithful

First recorded in 1350–1400; Middle English unfeithful, unfaithful; un- ¹ + faithful ( def. )

Example Sentences

He denied ever witnessing Epstein in the company of a minor and said he was never unfaithful to his wife.

From The Wall Street Journal

Once the Games began, they were humiliated again by another kind of cheating scandal involving an unfaithful biathlete.

From The Wall Street Journal

Then there’s the Norwegian biathlete who admitted to being unfaithful in a very public bid for forgiveness.

From The Wall Street Journal

"And three months ago, I made the biggest mistake of my life and I was unfaithful," he continued.

From Barron's

It’s not that she’s unfaithful to the material.

From Los Angeles Times

Related Words

• cheating
• untrue