spore sac vs sporangium

spore sac and sporangium both are nouns.

Word	Noun	Adjective	Verb	Adverb
spore sac	Yes	No	No	No
sporangium	Yes	No	No	No

As nouns, spore sac and sporangium are synonyms defined as:

Other synonyms of spore sac include spore case.

spore sac (noun)	sporangium (noun)
organ containing or producing spores	organ containing or producing spores