Skip to Content
Medical Term:


Pronunciation: kī′azm


  1. An intersection or crossing of two lines.
  2. In anatomy, a decussation or crossing of two fibrous bundles, such as tendons, nerves, or tracts.
  3. In cytogenetics, the site at which two homologous chromosomes make contact (thus appearing to be crossed), enabling the exchange of genetic material during the prophase stage of meiosis.

Synonym(s): chiasmaTA

[G. chiasma]

© Copyright 2017 Wolters Kluwer. All Rights Reserved. Review Date: Sep 19, 2016.