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Question 1 of 7
IS and ARE are both forms of which verb?

Origin of invalid

1
First recorded in 1635–45; from French invalide, from Latin invalidus “weak, feeble, infirm”; See in-3, valid

Other definitions for invalid (2 of 2)

invalid2
[ in-val-id ]
/ ɪnˈvæl ɪd /

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
First recorded in 1630–40; from Latin invalidus “weak, feeble”; see invalid1

OTHER WORDS FROM invalid

in·val·id·ly, adverbin·val·id·ness, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022

How to use invalid in a sentence

British Dictionary definitions for invalid (1 of 2)

invalid1
/ (ˈɪnvəˌliːd, -lɪd) /

noun
  1. a person suffering from disablement or chronic ill health
  2. (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 of invalid

invalidity, noun

Word Origin for invalid

C17: from Latin invalidus infirm, from in- 1 + validus strong

usage for invalid

It is best to avoid using the term invalid when referring to people with chronic illnesses or disabilities

British Dictionary definitions for invalid (2 of 2)

invalid2
/ (ɪnˈvælɪd) /

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 of invalid

invalidity (ˌɪnvəˈlɪdɪtɪ) or invalidness, nouninvalidly, adverb

Word Origin for invalid

C16: from Medieval Latin invalidus without legal force; see invalid 1
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medical definitions for invalid

invalid
[ ĭnvə-lĭd ]

n.
One who is incapacitated by a chronic illness or disability.
adj.
Incapacitated by illness or injury.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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