Meaning of cystidium

cys•tid•i•um

Pronunciation: (si-stid'ē-um), [key]
— pl. cys•tid•i•a
  1. (in certain basidiomycetous fungi) one of the large, inflated, sterile cells growing between the basidia and usually projecting beyond them.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.