Chiasma

n. crossing, intersecting, point of intersection (Genetics, Anatomy)

The term "Chiasma" is also sometimes used to refer to the Optic chiasm. A chiasma (Greek χίασμα, related to the Greek letter Χ) means "crossing." In anatomy, it refers to the point where two (or more) nerves or ligaments cross or intersect. In genetics, it is a technical term for the point where two chromatids are intertwined (interwoven) in a cell.
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Chiasma /chi·as·ma/ pl. chias´mata [L.] chiasm; in genetics, the points at which members of a chromosome pair are in contact during the prophase [more]Chiasma - Community and Resources

Noun
1. an intersection or crossing of two tracts in the form of the letter X
(synonym) chiasm, decussation
(hypernym) structure, anatomical structure, complex body part, bodily structure, body structure
(hyponym) optic chiasma, optic chiasm, chiasma opticum

n. chiasma, point of intersection (Genetics, Anatomy); chiasmus (Rhetoric)