ˌaməˈnäptərə̇n noun
( -s )
Etymology: aminopter oylglutamic + -in
: a yellow crystalline compound C 19 H 20 N 8 O 5 .2H 2 O used clinically as an antagonist to folic acid in the treatment of certain leukemias — called also 4-aminopteroylglutamic acid