arse around vs idle

arse around is not a noun while idle is a noun.

Word	Noun	Adjective	Verb	Adverb
arse around	No	No	Yes	No
idle	Yes	Yes	Yes	No

As verbs, idle is a hypernym of arse around; that is, idle is a word with a broader meaning than arse around:

Other hypernyms of arse around include laze, slug, stagnate.

arse around (noun)	idle (noun)
	the state of an engine or other mechanism that is idling

arse around (adjective)	idle (adjective)
	not in action or at work
	silly or trivial
	not in active use
	lacking a sense of restraint or responsibility
	not having a job
	not yielding a return
	without a basis in reason or fact

arse around (verb)	idle (verb)
indulge in horseplay	run disconnected or idle
be lazy or idle	be idle; exist in a changeless situation