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

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

From Los Angeles Times

During the trial, Holly has been portrayed by him to be a nasty, unfaithful girlfriend who had multiple boyfriends, this could not be further from the truth.

From BBC

Stewart said the act was “neither naughty nor unfaithful.”

From Salon

They divorced after he admitted to being unfaithful during the marriage.

From BBC

The construction worker was filmed tearfully pleading: "I swear to God, I am being so straight... I have not been unfaithful to her."

From BBC

Related Words

• cheating
• untrue