- invalid (adj.)
- 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. Hôtel des Invalides, home for old and disabled soldiers in Paris.