unfaithful

play
adjective un·faith·ful \ ˌən-ˈfāth-fəl \

Definition of unfaithful

:not faithful:
a :not adhering to vows, allegiance, or duty :disloyal
  • an unfaithful friend
b :not faithful to marriage vows
  • suspected her husband of being unfaithful
c :inaccurate, untrustworthy
  • an unfaithful copy of a document

unfaithfully

play \ˌən-ˈfāth-fə-lē\ adverb

unfaithfulness

noun

Examples of unfaithful in a Sentence

  1. colonists who later proved to be unfaithful to the cause of independence

Recent Examples of unfaithful from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'unfaithful.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of unfaithful

15th century


UNFAITHFUL Defined for English Language Learners

unfaithful

play
adjective

Definition of unfaithful for English Language Learners

  • : having a sexual relationship with someone who is not your wife, husband, or partner

  • : not accurate


UNFAITHFUL Defined for Kids

unfaithful

play
adjective un·faith·ful \ ˌən-ˈfāth-fəl \

Definition of unfaithful for Students

:not faithful :disloyal


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