INVALID Synonyms: 266 Similar and Opposite Words

invalid 1 of 3

adjective (1)

ˈin-və-ləd

Definition of invalid

as in fragile

chronically or repeatedly suffering from poor health an old and now invalid woman who rarely gets out anymore

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Relevance

Antonyms & Near Antonyms

invalid

2 of 3

adjective (2)

(ˌ)in-ˈva-ləd

as in null

having no legal or binding force the treaty is invalid once one side violates it

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Antonyms & Near Antonyms

as in erroneous

not being in agreement with what is true that's an invalid assumption on your part

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Antonyms & Near Antonyms

as in unreasonable

not using or following good reasoning an argument which has one untrue premise is invalid

Synonyms & Similar Words

Antonyms & Near Antonyms

as in unsupported

having no basis in reason or fact an invalid claim that can be easily disproved by the facts

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Antonyms & Near Antonyms

invalid

3 of 3

verb

as in to impair

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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 invalid

Adjective

Caldara called for the rail district and the secretary of state’s office to deem Issue 7A invalid. — Noelle Phillips, Denver Post, 7 Oct. 2026 But what was that invalid-fair-catch penalty on his next attempt? — Blair Kerkhoff, Kansas City Star, 5 Oct. 2026

Verb

If this is ascertained, the BBC quotes an LA attorney saying this would render Hackman’s will invalid, and mean his children could have a claim to the estate. — Caroline Frost, Deadline, 16 Mar. 2025 DeSantis's office has said all options are on the table for their fight, but a legal ruling invaliding the agreement that currently gives Disney near-total control of the district would be the easiest resolution for the governor's headache. — Jack Birle, Washington Examiner, 8 Apr. 2023 See All Example Sentences for invalid

Recent Examples of Synonyms for invalid

Adjective

Where Thomas is aloof and proud, Erika is prickly and sardonic, excellent tools for protecting a surprisingly fragile heart.

— Los Angeles Times, Los Angeles Times, 23 Oct. 2026
My childhood school in Denmark hadn’t been turned to rubble but into an emotional battlefield, a psychological groundhog’s day of explosive arguments, violent brawls—and brief, fragile truces that always shattered when the home bell rung.

— Literary Hub, Literary Hub, 23 Oct. 2026

Definition of fragile

Adjective

For one, null results—in this case, findings that are not unusual or revelatory—are still useful.

— Jackie Flynn Mogensen, Scientific American, 4 June 2026
However, in the face of an increasing number of null results, most notably in studies published in late 2025, most physicists now agree that this sterile neutrino doesn’t exist.

— Quanta Magazine, Quanta Magazine, 8 Apr. 2026

Definition of null

Adjective

Bisignano, a former Wall Street CEO who has been overhauling how the agency operates, also said SSA was working to fix erroneous records.

— Fernanda Tronco, Fortune, 20 Oct. 2026
In his own review of the case, Mandell failed to flag an erroneous jury instruction that four years later would lead to the conviction being overturned.

— Samantha Melamed, ProPublica, 13 Oct. 2026

Definition of erroneous

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

Nvidia has gone to great lengths to secure support from game publishers, but many titles remain unsupported at the time of writing.

— Joe Osborne, PC Magazine, 17 Oct. 2026
This case involved a restaurant owner accused of underreporting more than US$2 million in business receipts and claiming unsupported depreciation deductions on rental properties.

— Kaitlin Newkirk, The Conversation, 14 Oct. 2026

Definition of unsupported

Verb

Casa Brera has accommodations for the hearing impaired and wheelchair accessible showers.

— Condé Nast, Condé Nast Traveler, 22 Oct. 2026
In the brain, for example, elevated stress hormones can impair learning and memory by flooding the hippocampus with excitatory chemical signals.

— Maia Szalavitz, Scientific American, 20 Oct. 2026

Definition of impair

Adjective

The age-old advice of keeping your passwords secure and being wary of suspicious emails is more important than ever as hackers gain more sophisticated tools and use AI to find more of the internet’s weak points.

— Lisa Eadicicco, CNN Money, 26 Oct. 2026
Analysts expect profits and assets to cover the dividend through weaker timber periods.

— Sebastien Chasse, CNBC, 26 Oct. 2026

Definition of weak

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in vain

invalid

invalidate

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Style

“Invalid.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/invalid. Accessed 27 Oct. 2026.

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Synonyms of invalid

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