slay vs off

slay is not an adjective while off is an adjective.

Word	Noun	Adjective	Verb	Adverb
slay	No	No	Yes	No
off	No	Yes	Yes	Yes

As verbs, slay and off are synonyms defined as:

Other synonyms of slay include bump off, dispatch, hit, murder, polish off, remove.

slay (adjective)	off (adjective)
	not in operation or operational
	(of events) no longer planned or scheduled
	not performing or scheduled for duties
	in an unpalatable state
	below a satisfactory level

slay (verb)	off (verb)
kill intentionally and with premeditation	kill intentionally and with premeditation
to succeed greatly

slay (adverb)	off (adverb)
	at a distance in space or time
	from a particular thing or place or position (`forth' is obsolete)
	no longer on or in contact or attached