invalidate

Etymology

The Oxford dictionaries take it as borrowed from Medieval Latin invalidō (“to annul”), from its past participle stem,^[2][3] perhaps partly after French invalider, recorded from 1549.^[4][2] The OED gives the Latin verb only as a hypothetical type.^[4] Etymonline, Merriam-Webster Unabridged and Dictionary.com instead take it as formed from English invalid + -ate.^[5][6][7] Both explanations lead to Latin invalidus (“not strong, infirm, inadequate”), from in- (“not”) and validus (“strong”),^[5][3] which Etymonline traces to Proto-Indo-European *wal- (“to be strong”).^[5]

Earliest recorded meaning

To render invalid or of no effect: 1649, in the papers of E. Nicholas.^[4][6] Etymonline dates the word to the 1640s, and Dictionary.com to 1640–50.^[5][7]

Semantic evolution

The word has kept its meaning, applied both to things with legal force, such as a contract, and to arguments.^[4][2] Johnson (1755) defined it more broadly as "to weaken; to deprive of force or efficacy", with quotations from Boyle and Locke, where a consequence or testimony is invalidated.^[8] Merriam-Webster's Collegiate groups it with nullify, negate, annul and abrogate, as words for depriving something of effective existence.^[9]

Timeline

• 1649 – to destroy the validity or strength of something, especially to deprive it of legal effect.^[4][6]

Meanings

Verb

1. To make invalid; to deprive of legal force: A missing signature can invalidate a will.^[4][2][10]
2. To weaken or discredit something, such as an argument or claim.^[6][4][8]

Word family

• invalidation
• invalidator

Related words

• invalid
• valid
• validate
• validity

References

1. ^ a b Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
3. ^ a b Stevenson, Angus, ed. (2010), Oxford Dictionary of English, 3rd ed., Oxford: Oxford University Press
4. ^ a b c d e f g Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
5. ^ a b c d Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
6. ^ a b c d Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
7. ^ a b Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
8. ^ a b Johnson, Samuel (1755), A Dictionary of the English Language, London; 4th ed. 1773; Johnson's Dictionary Online, ed. Beth Rapp Young et al.
9. ^ Merriam-Webster's Collegiate Dictionary (2003), 11th ed., Springfield, Mass.: Merriam-Webster
10. ^ The World Book Dictionary (2015), Chicago: World Book