drop away vs drop off

drop away and drop off both are verbs.

Word	Noun	Adjective	Verb	Adverb
drop away	No	No	Yes	No
drop off	No	No	Yes	No

As verbs, drop away and drop off are synonyms defined as:

Other synonyms of drop away include fall away, slip.

drop away (verb)	drop off (verb)
fall to a lower standard	change from a waking to a sleeping state
	fall to a lower standard
	fall or diminish
	retreat
	remove (cargo, people, etc.) from and leave