The Collaborative International Dictionary of English v.0.48:

Physophorae \Phy*soph"o*r[ae]\, prop. n. pl. [NL., fr. Gr. fy^sa
   a bellows + fe`rein to bear.] (Zool.)
   An order of Siphonophora, furnished with an air sac, or
   float, and a series of nectocalyces. See Illust. under
   Nectocalyx.
   [1913 Webster]