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Synonyms

invalidate

American  
[in-val-i-deyt] / ɪnˈvæl ɪˌdeɪt /

verb (used with object)

invalidated, invalidating
  1. to render invalid; discredit.

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


invalidate British  
/ ɪnˈvælɪˌdeɪt /

verb

  1. to render weak or ineffective, as an argument

  2. 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

Other Word Forms

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

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.

Even more fundamentally, Jay pointed out that the attorney general’s theory would invalidate Florida’s adoption laws.

From Slate • May 13, 2026

They say the new guidance violates multiple federal laws, including laws that govern federal spending and rule changes, and are asking the federal court to immediately invalidate the guidance as unlawful.

From Los Angeles Times • Mar. 16, 2026

Trade Representative Jamieson Greer said the Court’s decision wouldn’t invalidate deals the U.S. has already struck.

From Barron's • Feb. 23, 2026

This does not invalidate gold or silver as long-term hedges.

From MarketWatch • Jan. 30, 2026

The half-broken mini blind that would surely invalidate their deposit if they ever moved out.

From "We'll Fly Away" by Bryan Bliss

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