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

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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 The singer gets back behind the wheel of the gold Trans Am an unfaithful friend stole from her all those years ago and revs up for a nuclear night out. — Larisha Paul, Rolling Stone, 26 Oct. 2026 In other words, some hallucinated or unfaithful answers originate before generation. — Patrick Dajos, Forbes.com, 23 Sep. 2026 Patrick testified and found himself at the center of an online swarm of sleuths and influencers dissecting every detail of the case, developing theories that portray him as uncaring, unfaithful and even the murderer of his children. — Ross Douthat, CBS News, 20 Sep. 2026 When the braids had five or more strands, however, the disk possibilities proliferated, guaranteeing the matrices were all unfaithful. — Lyndie Chiou, Scientific American, 24 July 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
  • The book is centered on a traitorous CIA officer who has found refuge with the Russian mafia with plans to kill Reece.
    — Peter White, Deadline, 5 Nov. 2026
  • 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
Definition of traitorous
Adjective
  • According to Rose, weeks without rain can force them to conserve water, while prolonged storms can leave them with less solar power and unreliable Wi-Fi.
    — Tereza Shkurtaj, PEOPLE, 9 Nov. 2026
  • If its data becomes outdated or its model fails to account for changing conditions, its predictions can become unreliable.
    — Kaif Shaikh, Interesting Engineering, 8 Nov. 2026
Definition of unreliable
Adjective
  • Lina Attalah, a co-founder and editor-in-chief of Mada Masr, is challenging a one-year prison sentence and a fine imposed in absentia on charges of operating a website without a license and spreading false news.
    — Arkansas Online, Arkansas Online, 12 Nov. 2026
  • Numerous European carriers were hit with false bomb threats last week, including Irish airlines Aer Lingus and Ryanair, Hungarian carrier Wizz Air and Polish Airlines.
    — Aliss Higham, MSNBC Newsweek, 11 Nov. 2026
Definition of false
Adjective
  • Also intertwined are ancient myths of warring city-states, the raw, moody poetry of John Keats, and the modern battle between a faithless husband and his wife, the poem’s raging speaker.
    — Merve Emre, New Yorker, 21 Oct. 2026
  • The French had said the British were faithless.
    — Literary Hub, Literary Hub, 20 May 2026
Definition of faithless
Adjective
  • Calvert’s campaign, meanwhile, labels Kim a RINO, or Republican in name only, a pejorative used to describe a disloyal conservative.
    — Dakota Smith, Los Angeles Times, 30 Oct. 2026
  • The president has essentially purged the House GOP ranks of those perceived to be disloyal.
    — ABC News, ABC News, 17 Oct. 2026
Definition of disloyal
Adjective
  • Besides, second terms--and especially their final two years--have proved treacherous for every recent president, including Reagan, who survived a major scandal involving arms sales to Iran.
    — Arkansas Online, Arkansas Online, 12 Nov. 2026
  • Except, counters Soll, that the placement of the giraffe is treacherous because the front door swings right in its path.
    — Leonora Epstein, Architectural Digest, 11 Nov. 2026
Definition of treacherous

Browse Nearby Words

unfaith
unfaithful
unfaithfulness
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Cite this Entry

“Unfaithful.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/unfaithful. Accessed 13 Nov. 2026.

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