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.
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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.
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