drifting vs aimless

drifting is a noun but aimless is not a noun.

Word	Noun	Adjective	Verb	Adverb
drifting	Yes	Yes	No	No
aimless	No	Yes	No	No

As adjectives, drifting and aimless are synonyms defined as:

drifting and aimless: continually changing especially as from one abode or occupation to another

Other synonyms of drifting include floating, vagabond, vagrant.

drifting (noun)	aimless (noun)
aimless wandering from place to place

drifting (adjective)	aimless (adjective)
continually changing especially as from one abode or occupation to another	aimlessly drifting
	continually changing especially as from one abode or occupation to another