Mec`o*nid"i*um (?), n. [NL., dim. of Gr. a poppy. So called in allusion to the shape of the seed capsules of the poppy.] Zool.
A kind of gonophore produced by hydroids of the genus Gonothyraea. It has tentacles, and otherwise resembles a free medusa, but remains attached by a ppedicel.
© Webster 1913.