WORD ORIGIN adjective not valid; without force or foundation; indefensible. deficient in substance or cogency; weak. void or without legal force, as a contract. Origin of invalid 2 1625–35;
Medieval Latin invalidus, Latin:
invalid 1 Related forms in·val·id·ly, adverb in·val·id·ness, noun
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for invalidly noun a person suffering from disablement or chronic ill health ( as modifier) an invalid chair adjective suffering from or disabled by injury, sickness, etc verb (tr) to cause to become an invalid; disable ( usually foll by out; often passive) mainly British to require (a member of the armed forces) to retire from active service through wounds or illness Derived Forms invalidity, noun Word Origin for invalid
C17: from Latin
invalidus infirm, from in- 1 + validus strong usage
It is best to avoid using the term
invalid when referring to people with chronic illnesses or disabilities adjective not valid; having no cogency or legal force logic (of an argument) having a conclusion that does not follow from the premises: it may be false when the premises are all true; not valid Derived Forms invalidity ( ˌɪnvəˈlɪdɪtɪ) or invalidness, noun invalidly, adverb Word Origin for invalid
C16: from Medieval Latin
invalidus without legal force; see invalid 1
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
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Word Origin and History for invalidly adj.1
"not strong, infirm," 1640s, from Latin
invalidus "not strong, infirm, weak, feeble," from in- "not" (see in- (1)) + validus "strong" (see valid). Specific meaning "infirm from sickness, disease, or injury" is from 1640s. n.
1709, originally of disabled military men, from
invalid (adj.1). Invalides is short for French Hôtel des Invalides, home for old and disabled soldiers in the 7th arrondissement of Paris. adj.2
"of no legal force," 1630s, from special use of Latin
invalidus (see invalid (adj.1)).
Online Etymology Dictionary, © 2010 Douglas Harper
n. One who is incapacitated by a chronic illness or disability. adj. Incapacitated by illness or injury.
The American Heritage® Stedman's Medical Dictionary
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