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 The researchers suspect that others were created by AI that either hallucinated or, just like the AI agents browsing their file, couldn’t distinguish between legitimate and illegitimate instructions. — Dan Goodin, ArsTechnica, 27 Aug. 2026 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 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

Runa’s incarceration – and death months after her release – is now the subject of a lawsuit brought by her mother against Hyogo Prefectural Police alleging unlawful arrest and detention.

— Hanako Montgomery, CNN Money, 24 Oct. 2026
Last month, the seizure was ruled unlawful by the California Supreme Court.

— Iris Kwok, Los Angeles Times, 24 Oct. 2026

Definition of unlawful

Adjective

On the surface, paying as low as 24 cents for an hour of streaming game time doesn’t sound completely unreasonable.

— Kyle Orland, ArsTechnica, 21 Oct. 2026
If Putin rejects the framework — or, more likely, demands unreasonable changes — then the world will at least know who blocked the fledgling peace effort.

— David Ignatius, Washington Post, 21 Oct. 2026

Definition of unreasonable

Adjective

So, too, was Capra’s, despite some misbegotten movies and his struggles with depression and other ailments.

— Los Angeles Times, Los Angeles Times, 27 Oct. 2026
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

Definition of misbegotten

Adjective

So far, the most plausible driver of recent declines in overdose deaths is a change in the illicit drug supply.

— J. Travis Donahoe, STAT, 23 Oct. 2026
But how and through whom the money flowed into the Alpha account revealed that it was intended to remain secret, more akin to a covert and illicit scheme, given that it was managed in part by a senior advisor to the president of the United States.

— Matthew Cole, Vanity Fair, 22 Oct. 2026

Definition of illicit

Adjective

Giving any person a $100 million contract to coach a college athletic team is irrational.

— Letters to the Editor, The Orlando Sentinel, 28 Oct. 2026
The industrial revolutions of the past produced enormous value alongside bankruptcies, dislocations, and periods of irrational exuberance.

— Brian Solis, Forbes.com, 5 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

The police spokesperson said Perez was taken into custody without incident and charged with menacing and criminal possession of a weapon.

— Iris Kwok, Los Angeles Times, 27 Oct. 2026
The leader of one of Haiti’s most powerful criminal organizations said the Salvadorans were killed in territory controlled by Chen Mechan, an allied gang.

— Widlore Mérancourt, Washington Post, 26 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 28 Oct. 2026.

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Synonyms of illegitimate

adjective

Example Sentences

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