Synonyms

invalidate

American

[in-val-i-deyt] / ɪnˈvæl ɪˌdeɪt /

verb (used with object)

to render invalid; discredit.

Synonyms:

rebut, refute, disprove, impair, weaken
to deprive of legal force or efficacy; nullify.

invalidate British

/ ɪnˈvælɪˌdeɪt /

verb

to render weak or ineffective, as an argument
to take away the legal force or effectiveness of; annul, as a contract

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

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Etymology

Origin of invalidate

First recorded in 1640–50; invalid ² + -ate ¹

Explanation

If administrators find out that students cheated on a test, the school might invalidate their class grades. To invalidate means to cancel something or make it void, as if it never happened. In invalidate you see the word valid which means true or correct. When you invalidate something you are making it less true, less official, or less correct. If you buy something that doesn't work properly and then try to fix it yourself, you invalidate the warranty. If you have a wacky theory that cars grow from trees, your teacher might invalidate your theory by taking you on a tour of an auto factory.

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Vocabulary lists containing invalidate

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Markets evolve quickly, and subsequent price action can strengthen, invalidate, or reshape even well-reasoned calls.

From Barron's • Jun. 17, 2026

At that time, Infantino suggested such a move could invalidate a country's World Cup hosting rights.

From BBC • Jun. 9, 2026

He sought to invalidate the surrogacy contract as unconstitutional, denying the couple’s claim of parentage over their child.

From Slate • May 13, 2026

One doctor never examined her, while another barely spoke to her; either of these issues could invalidate competency declarations and expose medical misconduct, fraud and/or conspiracy.

From MarketWatch • Mar. 19, 2026

“Like, that doesn’t invalidate it, right? Your parents can get divorced and it doesn’t mean anything in the long run.”

From "Far from the Tree" by Robin Benway

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023