Simple Definition of invalidate
: to weaken or destroy the effect of (something)
: to show or prove (something) to be false or incorrect
Examples of invalidate in a sentence
actions that will invalidate the contract
The study invalidates earlier theories.
factors that may invalidate the test results
First Known Use of invalidate
Synonym Discussion of invalidate
INVALIDATE Defined for Kids
Definition of invalidate for Students
: to weaken or destroy the effect of <The phony signature invalidated the contract.>
Seen and Heard
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