from The American Heritage® Dictionary of the English Language, 5th Edition.
- noun Anatomy A crossing or intersection of two tracts, as of nerves or ligaments.
- noun Genetics The point of contact between paired chromatids during meiosis, resulting in a cross-shaped configuration and representing the cytological manifestation of crossing over.
from The Century Dictionary.
- noun Same as
from Wiktionary, Creative Commons Attribution/Share-Alike License.
- noun anatomy A
crossingof two nerves, ligamentsetc.
- noun genetics, cytology The
contact pointbetween the two chromatidsof a chromosomeduring meiosis.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- noun an intersection or crossing of two tracts in the form of the letter X
from The American Heritage® Dictionary of the English Language, 4th Edition
from Wiktionary, Creative Commons Attribution/Share-Alike License
In this early poem – the first one in his Selected Poems – Heaney uses a rhetoric figure that for a considerable period would be his trademark: the 'chiasma', or crossing of themes.
Because the optic chiasma had been cut, using their left eye they were unaware of the left half of the field of view of the screen the virtual image is reversed.
Finally, one of my favorite poetic and rhetorical tricks is the chiasma.
ANS is largely under hypothalamic control which is situated very close to optic chiasma sixth chakra or ajna chakra.
Shakespeare's is an interesting line, but a good chiasma is a literary firework -- an "OH!" moment -- and Bill Clinton's delivered a great one Wednesday night:
 He impressed him as a chiasma, i.e., in the form of the letter ch upon the universe.
A chiasma so located starts its terminalization process to reach the end of the arm.
It is enough to induce chromosome breakage should the terminalization process be blocked before the terminalizing chiasma reaches the end of the arm of a chromosome.
The fibers thus form an X shape; and the structure is the optic chiasma (ky~az'muh), because the Greek letter "chi" looks like our X (see illustration, p. 274).
In front, the cisterna interpeduncularis extends forward across the optic chiasma, forming the cisterna chiasmatis, and on to the upper surface of the corpus callosum, for the arachnoid stretches across from one cerebral hemisphere to the other immediately beneath the free border of the falx cerebri, and thus leaves a space in which the anterior cerebral arteries are contained.