Source : Webster's Revised Unabridged Dictionary (1913)

Oosporangium \O`["o]*spo*ran"gi*um\, n.; pl. L.
   {O["o]sporangia}, E. {O["o]sporangiums}. [NL., fr. Gr. ? an
   egg + ? vessel.] (Bot.)
   An o["o]gonium; also, a case containing oval or rounded
   spores of some other kind than o["o]spores.