Skip to Content


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]

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

© Copyright 2018 Wolters Kluwer. All Rights Reserved. Review date: Sep 19, 2016.