passable vs adequate

passable and adequate both are adjectives.

Word	Noun	Adjective	Verb	Adverb
passable	No	Yes	No	No
adequate	No	Yes	No	No

As adjectives, passable and adequate are synonyms defined as:

Other synonyms of passable include fair to middling, tolerable.

passable (adjective)	adequate (adjective)
able to be passed or traversed or crossed	having the requisite qualities or resources to meet a task
about average; acceptable	about average; acceptable
	sufficient for the purpose