ILLEGITIMATE Synonyms: 168 Similar and Opposite Words

illegitimate

adjective

ˌi-li-ˈji-tə-mət

Definition of illegitimate

as in spurious

born to a father and mother who are not married despite being illegitimate, Alexander Hamilton rose to greatness

Synonyms & Similar Words

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Antonyms & Near Antonyms

legitimate

as in illegal

contrary to or forbidden by law an illegitimate use of campaign contributions for personal expenses

Synonyms & Similar Words

Antonyms & Near Antonyms

as in unreasonable

not using or following good reasoning made several illegitimate inferences

Synonyms & Similar Words

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 illegitimate Internet discussions portrayed the SPLC as a politically motivated or illegitimate actor. — Art Jipson, The Conversation, 20 Aug. 2026 Holding an incomplete vote, or one that feeds into any narrative of the winner being illegitimate, would be a tremendous gift to Moscow. — Nick Paton Walsh, CNN Money, 19 Aug. 2026 Russian President Vladimir Putin, who has balked at negotiating a peace deal directly with Zelenskyy, asserts that the Ukrainian president is an illegitimate leader because his term expired in 2024. — Barry Hatton, Chicago Tribune, 19 Aug. 2026 Federal judges have quashed many of the subpoenas as illegitimate efforts to intimidate providers into ending care. — ABC News, 14 Aug. 2026 See All Example Sentences for illegitimate

Recent Examples of Synonyms for illegitimate

Adjective

To get to the bottom of the mystery of the article’s spurious dating, Cade and a team of researchers from around the globe sifted through historic reports and observations of geomagnetic activity to set the record straight.

— Mike McRae October 15, New Atlas, 16 Oct. 2026
These spurious claims about childhood vaccines will only increase vaccine hesitation with harmful results.

— Sun Sentinel Editorial Board, Sun Sentinel, 13 Aug. 2026

Definition of spurious

Adjective

But Michael Edney, who worked at the OLC under Bush, said the opinion’s reading of executive privilege was not unreasonable, given the importance that some presidents place on outside consultation.

— Perry Stein, Washington Post, 18 Oct. 2026
Both sides have accused each other of being unreasonable and of ignoring practical concerns about voting and election security, though in very different ways.

— Kevin Rector, Los Angeles Times, 17 Oct. 2026

Definition of unreasonable

Adjective

As an 'artificial friend' purchased for an ailing teen, Jenna Ortega tries hard to illuminate this misbegotten Kazuo Ishiguro adaptation, but Waititi's decision to play it for strained, whimsical comedy is ruinous.

— Guy Lodge, Variety, 17 Oct. 2026
Instead of delighting fans by paying loving homage to the movies or winning over newcomers with an exciting fresh take on the material, the show fails on both fronts, swinging wildly from one misbegotten idea to the next.

— Louis Peitzman, Vulture, 15 Oct. 2026

Definition of misbegotten

Adjective

From December 2024 to May 2025, the international law enforcement body Interpol conducted Operation Pangea XVII, in which authorities in 90 countries seized more than 50 million doses of illicit pharmaceuticals.

— Andrew Yockey, Fortune, 15 Oct. 2026
Participants were also asked about their alcohol consumption, smoking and illicit drug use.

— New Atlas, New Atlas, 14 Oct. 2026

Definition of illicit

Adjective

The industrial revolutions of the past produced enormous value alongside bankruptcies, dislocations, and periods of irrational exuberance.

— Brian Solis, Forbes.com, 5 Oct. 2026
If anyone can reconstruct Apéry’s reasoning, the odd values of zeta may finally be proven irrational.

— Lyndie Chiou, Scientific American, 2 Oct. 2026

Definition of irrational

Adjective

His adopted brother, Ken Masters (Noah Centineo) has devolved into a party machine who often winds up on MTV’s spring break coverage.

— Mike Ryan, IndieWire, 16 Oct. 2026
Lucas Museum Chief Executive Tracey Bates sees another fit between the institution and its adopted city.

— Jane Horowitz, Los Angeles Times, 10 Sep. 2026

Definition of adopted

Adjective

Homeland Security Investigations agents also interviewed Adawag last week, according to the criminal complaint filed against her.

— Mathew Miranda, Sacbee.com, 20 Oct. 2026
Martin Zummach, an attorney who represents the officer who fired the shot that killed Kohen, says the attorney general's findings cleared his client of criminal wrongdoing.

— SOPHIE BATES, Arkansas Online, 20 Oct. 2026

Definition of criminal

Browse Nearby Words

illegitimacy

illegitimate

ill-fated

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“Illegitimate.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/illegitimate. Accessed 21 Oct. 2026.

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Synonyms of illegitimate

adjective

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