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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

  • invalidation noun
  • invalidator noun

Etymology

Origin of invalidate

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

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.

A finding of undue influence can invalidate a will or trust if your grandmother was pressured, manipulated or dependent on your mother.

From MarketWatch • Mar. 30, 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

US District Judge Royce Lamberth endorsed Revolution Wind's request to invalidate the US Interior Department's move to suspend the project off the coast of Rhode Island.

From Barron's • Jan. 12, 2026

In 2022, however, the American Journal of Therapeutics, which had published the study, warned that suspicious data “appears to invalidate the findings” regarding ivermectin’s potential to decrease deaths.

From Salon • Dec. 15, 2025

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

From "We'll Fly Away" by Bryan Bliss