functional vs operable

functional and operable both are adjectives.

Word	Noun	Adjective	Verb	Adverb
functional	No	Yes	No	No
operable	No	Yes	No	No

As adjectives, functional and operable are synonyms defined as:

Other synonyms of functional include operational, usable, useable.

functional (adjective)	operable (adjective)
designed for or capable of a particular function or use	capable of being treated by surgical operation
involving or affecting function rather than physiology	usable for a specific purpose
relating to or based on function especially as opposed to structure	fit or ready for use or service
(of e.g. a machine) performing or capable of performing
designed for or adapted to a function or use
fit or ready for use or service