chiasma
Concise Oxford English Dictionary © 2008 Oxford University Press:
chiasma /kʌɪˈazmə, kɪ-/
▶noun (pl. chiasmata /-tə/)
- 1 (also optic chiasma) Anatomy the X-shaped structure formed at the point below the brain where the two optic nerves cross over each other.
- 2 Biology a point at which paired chromosomes remain in contact during the first metaphase of meiosis.
– origin C19: mod. L., from Gk chiasma ‘crosspiece, cross-shaped mark’, from khiazein ‘mark with the letter chi’.
'chiasma' also found in these Oxford entries:
