ˈterəˌdēn, -_d ə n noun
( -s )
Etymology: International Scientific Vocabulary pter- + -id + -ine; originally formed as German pteridin; from its being a factor in the pigments of butterfly wings
: a yellow crystalline bicyclic base C 6 H 4 N 4 that is a fundamental constituent in important natural products (as folic acid, leucopterin, xanthopterin); 1,3,5,8-tetra-aza-naphthalene