acinus vs sac

acinus and sac both are nouns.

Word	Noun	Adjective	Verb	Adverb
acinus	Yes	No	No	No
sac	Yes	No	No	No

As nouns, sac is a hypernym of acinus; that is, sac is a word with a broader meaning than acinus:

acinus (noun)	sac (noun)
one of the small sacs or saclike dilations in a compound gland	a structure resembling a bag in an animal
one of the small drupes making up an aggregate or multiple fruit like a blackberry	a case or sheath especially a pollen sac or moss capsule
	an enclosed space