The Collaborative International Dictionary of English v.0.48:

Ooecium \O*oe"ci*um\, n.; pl. Ooecia. [NL., fr. Gr. w,'o`n an
   egg + ? a house.] (Zool.)
   One of the special zooids, or cells, of Bryozoa, destined to
   receive and develop ova; an ovicell. See Bryozoa.
   [1913 Webster]