• (chiasma) An anatomical intersection or crossing of two tracts, such as with nerve or ligament fibers.
  NCI Thesaurus
  U.S. National Cancer Institute, 2021
• An anatomic structure formed by the crossing of the two optic nerves under the hypothalamus.
  NCI Thesaurus
  U.S. National Cancer Institute, 2021
• An anatomy term for an X-shaped crossing (for example, of nerves or tendons).
  NCI Dictionary of Cancer Terms
  U.S. National Cancer Institute, 2021
• Nerve trunk which is continuous with right and left optic nerves and right and left optic tracts.
  Foundational Model of Anatomy
  University of Washington, 2017
• The place in the brain where some of the optic nerve fibers coming from one eye cross optic nerve fibers from the other eye.
  NCI Dictionary of Cancer Terms
  U.S. National Cancer Institute, 2021
• The X-shaped structure formed by the meeting of the two optic nerves. At the optic chiasm the fibers from the medial part of each retina cross to project to the other side of the brain while the lateral retinal fibers continue on the same side. As a result each half of the brain receives information about the contralateral visual field from both eyes.
  NLM Medical Subject Headings
  U.S. National Library of Medicine, 2021
• (optic chiasma) Hypothalamic structure formed by the crossing of optic nerve fibers from the medial half of each retina.
  CRISP Thesaurus
  National Institutes of Health, 2006