Source : Webster's Revised Unabridged Dictionary (1913)

Chalaza \Cha*la"za\, n.; pl. E. {Chalazas}, L. {Chalaz[ae]}.
   [NL., fr. Gr. ? hail, pimple.]
   1. (Bot.) The place on an ovule, or seed, where its outer
      coats cohere with each other and the nucleus.

   2. (Biol.) A spiral band of thickened albuminous substance
      which exists in the white of the bird's egg, and serves to
      maintain the yolk in its position; the treadle.

Source : WordNet®

chalazae
     See {chalaza}

chalaza
     n 1: basal part of a plant ovule opposite the micropyle; where
          integument and nucellus are joined
     2: one of two spiral bands of tissue connecting the egg yolk to
        the enclosing membrane at either end of the shell
     [also: {chalazae} (pl)]