English
functional
From function + -al.
A compound of function + -al
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 In good working order.
Language periods are conventional ranges, not dates for this word.
Etymograph / functional