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 After so many years as the good guy, Klein is leaning into his dark side, taking on roles like the big bad Cicada on CW’s The Flash, and as JoAnna Garcia Swisher’s unfaithful ex-husband on the Netflix series Sweet Magnolias. — Gwen Ihnat, Entertainment Weekly, 9 July 2026 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 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
  • Companies which produce dangerous or unreliable products quickly become unpopular and unprofitable.
    — Max Harden, The Orlando Sentinel, 29 Oct. 2026
  • Google responded by developing its own AI features, including its notoriously unreliable AI Overviews, and prominently integrating them into its search engine.
    — Frank Landymore, Futurism, 29 Oct. 2026
Definition of unreliable
Adjective
  • The men stopped short of signing the oath required for vouching, but Moriarty said that giving false names and starting the process was enough to justify the felony charges.
    — Mark Vancleave, Los Angeles Times, 29 Oct. 2026
  • Bhengura faces a maximum of five years in prison on the false statements of citizenship in order to register to vote count and a maximum of one year in prison on the voting by an alien in a federal election count.
    — Emerson Clarridge, Fort Worth Star-Telegram, 29 Oct. 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
  • The president has essentially purged the House GOP ranks of those perceived to be disloyal.
    — ABC News, ABC News, 17 Oct. 2026
  • Directors feared that challenging the CEO publicly would be perceived as disloyal to the very leadership that had appointed them.
    — Albana Vrioni, Forbes.com, 28 Sep. 2026
Definition of disloyal
Adjective
  • Last month, the Coast Guard and Customs encountered several migrant ventures, some deadly, off the Dominican Republic and in the treacherous Mona Pass, between Hispaniola and Puerto Rico.
    — David Goodhue, Miami Herald, 29 Oct. 2026
  • Time is running out for a Republican Party led astray by a president whose treacherous behavior mimics those assigned to the lowest level of Dante’s hell.
    — Bob Kustra, Chicago Tribune, 22 Oct. 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 30 Oct. 2026.

Copy Citation
Love words? Need even more definitions?

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

Last Updated: - Updated example sentences

More from Merriam-Webster

Word of the Day

Listen to the pronunciation of reticent

See Definitions and Examples »

Popular in Grammar & Usage

See More

How to Use 'Who' vs. 'Whom'

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

'Affect' vs. 'Effect'

'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

The Longest Long Words List

9 Words That Sound Like Insults But Aren't

Pwn, Skibidi, Girlboss and Other Words Added to the 2026 Scrabble Dictionary

The Words of the Week - Oct. 30

12 Lovely and Unusual Words for the Natural World
See More

Popular

See More

How to Use 'Who' vs. 'Whom'

The Longest Long Words List

9 Words That Sound Like Insults But Aren't
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
different halloween monsters in silhouette
A Monstrous Vocab Quiz Words That Go Bump in the Night
See All