leptosporangium vs spore sac

leptosporangium and spore sac both are nouns.

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

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

leptosporangium: a sporangium formed from a single epidermal cell; characteristic of the Filicales or of almost all modern ferns
spore sac: organ containing or producing spores

Other hypernyms of leptosporangium include sporangium, spore case.

leptosporangium (noun)	spore sac (noun)
a sporangium formed from a single epidermal cell; characteristic of the Filicales or of almost all modern ferns	organ containing or producing spores