substantia nigra

sub·stan·tia ni·gra

noun
\səb-ˌstan-chē-ə-ˈnī-grə, -ˈnig-rə\

plural sub·stan·ti·ae ni·grae \-chē-ˌē-ˈnī-(ˌ)grē, -ˈnig-(ˌ)rē\

Definition of SUBSTANTIA NIGRA

: a layer of deeply pigmented gray matter situated in the midbrain and containing the cell bodies of a tract of dopamine-producing nerve cells whose secretion tends to be deficient in Parkinson's disease