unfaithful

[ uhn-feyth-fuhl ]
/ ʌnˈfeɪθ fəl /

adjective

not faithful; false to duty, obligation, or promises; faithless; disloyal.
not sexually faithful to a spouse or lover.
not accurate or complete; inexact: an unfaithful translation.
Obsolete. unbelieving; infidel.

Origin of unfaithful

First recorded in 1350–1400, unfaithful is from the Middle English word unfeithful. See un-1, faithful

OTHER WORDS FROM unfaithful

un·faith·ful·ly, adverb un·faith·ful·ness, noun

Example sentences from the Web for unfaithful

British Dictionary definitions for unfaithful

unfaithful
/ (ʌnˈfeɪθfʊl) /

adjective

not true to a promise, vow, etc
not true to a wife, husband, lover, etc, esp in having sexual intercourse with someone else
inaccurate; inexact; unreliable; untrustworthy unfaithful copy
obsolete not having religious faith; infidel
obsolete not upright; dishonest

Derived forms of unfaithful

unfaithfully, adverb unfaithfulness, noun