The Collaborative International Dictionary of English v.0.48:

Dispermous \Di*sper"mous\ (d[-i]*sp[~e]r"m[u^]s), a. [Gr. di- =
   dis + spe`rma seed, fr. spei`rein to sow: cf. F. disperme.]
   (Bot.)
   Containing only two seeds; two-seeded.
   [1913 Webster]