English
truth-functional
From truth + function + -al.
A compound of truth + function + -al
Proto-Germanic *triwwiþō ‘truth, promise’
Proto-West Germanic *triuwiþu
Old English trēowþ ‘truth, good faith’
Middle English treuthe ‘loyalty, truth’
English truth
Proto-Indo-European *bʰewg- ‘to enjoy’
…
Latin fungor ‘to perform’
Latin fūnctiō ‘performance’
Old French fonction
Middle French function
English function
Today it means
adj Of or relating to a truth function; having a truth value that depends solely on the truth values of its components.
Language periods are conventional ranges, not dates for this word.
Etymograph / truth-functional