Where integument and nucellus are joined

• One of two spiral bands of tissue connecting the egg yolk to the enclosing membrane at either end of the shell
• Basal part of a plant ovule opposite the micropyle

Wikipedia Word definitions in Wikipedia
Chalaza is a genus of mites in the family Laelapidae .

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

The Collaborative International Dictionary Word definitions in The Collaborative International Dictionary
Chalaza \Cha*la"za\, n.; pl. E. Chalazas , L. Chalaz[ae] . (Bot.) The place on an ovule, or seed, where its outer coats cohere with each other and the nucleus. (Biol.) A spiral band of thickened albuminous substance which exists in the white of the bird's ...

Wiktionary Word definitions in Wiktionary
n. 1 (context zoology English) One of the two spiral bands which attach the yolk of an egg to the eggshell, suspending it in the egg white. 2 (context botany English) The location where the nucellus attaches to the integuments, opposite the micropyle.