Source : Webster's Revised Unabridged Dictionary (1913)

Corm \Corm\ (k[^o]rm), n. [See {Cormus}.]
   1. (Bot.) A solid bulb-shaped root, as of the crocus. See
      {Bulb}.

   2. (Biol.) Same as {Cormus}, 2.

Source : WordNet®

corm
     n : solid swollen underground bulb-shaped stem or stem base and
         serving as a reproductive structure