The Collaborative International Dictionary of English v.0.48:
Synoecious \Syn*oe"cious\, a. [Pref. syn- + Gr. ? house.] (Bot.) Having stamens and pistil in the same head, or, in mosses, having antheridia and archegonia on the same receptacle. [1913 Webster]WordNet (r) 3.0 (2006):
synoecious adj 1: having male and female reproductive organs mixed in the same gametoecium [syn: synoicous, synoecious]