The definition of an invalid is a sick, weak person.(noun)
An example of an invalid is a feeble old woman in a hospital who cannot walk.
Invalid is defined as not correct or provable or not legally recognized.(adjective)
See invalid in Webster's New World College Dictionary
Origin: Fr invalide < L invalidus, feeble: see in- & valid
Origin: L invalidus
See invalid in American Heritage Dictionary 4
Origin: From invalid2 (influenced by French invalide, sickly, infirm).
Origin: Latin invalidus, weak
Origin: : in-, not; see in-1
Origin: + validus, strong (from valēre, to be strong; see wal- in Indo-European roots).
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