chiasma

chi·as·ma

noun \kī-ˈaz-mə, kē-\

plural chi·as·ma·ta \-mət-ə\

Definition of CHIASMA

1

: an anatomical intersection or decussation—see optic chiasma

2

: a cross-shaped configuration of paired chromatids visible in the diplotene of meiotic prophase and considered the cytological equivalent of genetic crossing-over

—chi·as·mat·ic \ˌkī-əz-ˈmat-ik, ˌkē-\ adjective