The Collaborative International Dictionary of English v.0.48:

Sporophore \Spo"ro*phore\ (sp[=o]"r[-o]*f[=o]r), n. [Spore + Gr.
   fe`rein to bear.] (Bot.)
   (a) A placenta.
   (b) That alternately produced form of certain cryptogamous
       plants, as ferns, mosses, and the like, which is
       nonsexual, but produces spores in countless numbers. In
       ferns it is the leafy plant, in mosses the capsule. Cf.
       Oophore.
       [1913 Webster]

WordNet (r) 3.0 (2006):

sporophore
    n 1: a spore-bearing branch or organ: the part of the thallus of
         a sporophyte that develops spores; in ferns and mosses and
         liverworts is practically equivalent to the sporophyte