chiasma: Meaning and Definition of

chi•as•ma

Pronunciation: (kī-az'mu), [key]
— pl. -mas, -ma•ta
  1. a crossing or decussation, as that of the optic nerves at the base of the brain.
  2. a point of overlap of paired chromatids at which fusion and exchange of genetic material take place during prophase of meiosis.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.
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