unfaithful

adjective

ˌən-ˈfāth-fəl How to pronounce unfaithful (audio)
Definition of unfaithfulnext
as in traitorous
not true in one's allegiance to someone or something colonists who later proved to be unfaithful to the cause of independence

Synonyms & Similar Words

Relevance

Antonyms & Near Antonyms

Example Sentences

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Recent Examples of unfaithful Nyong’o also plays Clytemnestra, the unfaithful wife of Agamemnon, whom Clytemnestra and her lover, Aegisthus, murder. — Encyclopedia Britannica, 1 July 2026 In Strangers on a Train, Rogers played Guy's unfaithful wife, whom Bruno offers to kill. — Emily Blackwood, PEOPLE, 29 June 2026 Platner is also an unfaithful spouse who mistreats women. — Chris Roemer, Baltimore Sun, 25 June 2026 Starring Yakusho Koji, the film follows a man released on parole after killing his unfaithful wife. — Naman Ramachandran, Variety, 13 May 2026 See All Example Sentences for unfaithful
Recent Examples of Synonyms for unfaithful
  1. traitorous
  2. unreliable
  3. false
  4. faithless
  5. disloyal
  6. treacherous
Adjective
  • Telemachus’ lone contribution is killing Melanthius, the traitorous Ithacan farmhand, thus preventing him from continuing to arm the suitors.
    — Marlow Stern, Variety, 17 July 2026
  • And at the very center of Hell is Satan himself, the traitorous Archangel Lucifer, depicted as a monstrous creature with wings and three heads.
    — Keith Cooper, Space.com, 11 May 2026
Definition of traitorous
Adjective
  • This is encouraging — trustworthy system should be able to pump the breaks and realize when data inputs are too unreliable to make accurate estimations.
    — Euan Ashley, STAT, 1 Oct. 2026
  • The ruler who turns to AI to reduce a dependence on unreliable humans may end up relying, more blindly than before, on the few AI specialists who keep the system running.
    — Seva Gunitsky, Foreign Affairs, 1 Oct. 2026
Definition of unreliable
Adjective
  • Frankel also faces investment adviser fraud and false-statement counts over SEC filings that allegedly concealed his conviction and a Finra suspension.
    — Amanda Gerut, Fortune, 1 Oct. 2026
  • Klobuchar noted the similarities in Atlanta’s and Iowa’s team names and accused Schmitt of relying on false information to suggest Smith had secretly traveled to Atlanta.
    — Claire Carter, The Washington Examiner, 30 Sep. 2026
Definition of false
Adjective
  • The French had said the British were faithless.
    — Literary Hub, Literary Hub, 20 May 2026
  • Consumed by rage and betrayal, Eleanor is driven to take a bloody, supernatural revenge upon her faithless husband.
    — Robert Lang, Deadline, 27 Dec. 2025
Definition of faithless
Adjective
  • Business leaders keep asking why young workers seem disloyal, disengaged, quick to walk.
    — Lori Janke, Fortune, 31 Aug. 2026
  • Netanyahu is not on record as making that remark, but the slogan reflects a broader narrative promoted by Iranian hardliners, portraying women who do not wear the hijab as, at the very least, disloyal to their country.
    — Tim Lister, CNN Money, 23 Aug. 2026
Definition of disloyal
Adjective
  • Many of these migrants navigate the passage on makeshift boats that can capsize in treacherous waters.
    — Landon Mion, FOXNews.com, 29 Sep. 2026
  • The hillside was too treacherous for anybody to carry a litter up it, and a helicopter couldn’t descend in such a narrow airspace.
    — Peter Hessler, New Yorker, 28 Sep. 2026
Definition of treacherous

Browse Nearby Words

unfaith
unfaithful
unfaithfulness
See all Nearby Words

Cite this Entry

“Unfaithful.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/unfaithful. Accessed 2 Oct. 2026.

Copy Citation
Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

More from Merriam-Webster

Word of the Day

Listen to the pronunciation of heterodox

See Definitions and Examples »

Popular in Grammar & Usage

See More

Do You Need a New Language Peeve?

More Commonly Mispronounced Words

Merriam-Webster’s Great Big List of Words You Love to Hate

'A' or 'an'? What about before 'h'? An Indefinite Article Guide

Why is '-ed' sometimes pronounced at the end of a word?
See More

Popular in Wordplay

See More

7 Great Ways to Say 'Great'

The Longest Long Words List

9 Words That Sound Like Insults But Aren't

The Words of the Week - Oct. 2

16 Food Words Recently Added to the Dictionary
See More

Popular

See More

Do You Need a New Language Peeve?

7 Great Ways to Say 'Great'

The Longest Long Words List
See More

Games & Quizzes

See All
Play Quordle: Guess all four words in a limited number of tries. Each of your guesses must be a real 5-letter word.
Quordle Can you solve 4 words at once?
Play Blossom: Solve today's spelling word game by finding as many words as you can using just 7 letters. Longer words score more points.
Blossom Pick the best words!
Play Missing Letter: a crossword with a twist. Each of the 25 puzzle words start with a different letter of the alphabet. Which letter is missing?
The Missing Letter A daily crossword with a twist
name tags
Words Named After People Quiz Find out who’s behind "leotard," "morphine," an...
See All