Main Entry: ¹in·val·id

Pronunciation: \(ˌ)in-ˈva-ləd\

Function: adjective

Etymology: Latin invalidus weak, from in- + validus strong — more at valid

Date: 1542

: not valid: a : being without foundation or force in fact, truth, or law <an invalid assumption> <declared the will invalid> b : logically inconsequent

— in·val·id·ly \-lē\ adverb