Source : Webster's Revised Unabridged Dictionary (1913)

Sclerotium \Scle*ro"ti*um\, n.; pl. {Sclerotia}. [NL., fr. Gr.
   sklhro`s hard.]
   1. (Bot.) A hardened body formed by certain fungi, as by the
      {Claviceps purpurea}, which produces ergot.

   2. (Zo["o]l.) The mature or resting stage of a plasmodium.

Source : WordNet®

sclerotia
     See {sclerotium}