Definition of

Invalid

  1. (noun, person) someone who is incapacitated by a chronic illness or injury
  2. (verb, body) injure permanently
  3. (verb, social) force to retire, remove from active duty, as of firemen
  4. (adj, all) no longer valid
  5. (adj, all) having no cogency or legal force
    an invalid driver's license

via WordNet, Princeton University

Synonyms of Invalid

disable, handicap, incapacitate, shut-in

Antonyms of Invalid

valid

Alternate forms of Invalid

Derivations: invalid, invalidity, invalidness

Hyponyms: hock

Hypernyms: diseased person, injure, remove, sick person, sufferer, wound

Origin of the word Invalid

  1. 1635, "not strong, infirm," also "of no legal force," from L. invalidus "not strong, infirm, weak, feeble," from in- "not" + validus "strong." Meaning "infirm from sickness, disease, or injury" is from 1642. The noun is first recorded 1704, originally of disabled military men. Invalidate is from 1649. Invalides is short for Fr. H?tel des In… more

via Online Etymology Dictionary, ©2001 Douglas Harper

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