astir vs about

astir and about both are adjectives.

Word	Noun	Adjective	Verb	Adverb
astir	No	Yes	No	No
about	No	Yes	No	Yes

As adjectives, astir and about are synonyms defined as:

astir (adjective)	about (adjective)
on the move	on the move
out of bed

astir (adverb)	about (adverb)
	(of quantities) imprecise but fairly close to correct
	in the area or vicinity
	in or to a reversed position or direction
	in rotation or succession
	used of movement to or among many different places or in no particular direction
	(of actions or states) slightly short of or not quite accomplished; all but
	all around or on all sides