Entry 1 sense Webster, 1913 Sporangium /(spō̇*răn"jĭ*ŭm)/ · Spo·ran·gi·um · IPA /spəˈɹænd͡ʒɪəm/ 01 n. A spore case in the cryptogamous plants, as in ferns, etc. pl. Sporangia ((spō̇*răn"jĭ*ȧ)) 1. A spore case in the cryptogamous plants, as in ferns, etc.(Bot.)