Main Entry: py·rim·i·dine

Pronunciation: \pī-ˈrim-ə-ˌdēn, pə-\

Function: noun

1 : a weakly basic organic compound C₄H₂N₂ of penetrating odor that is composed of a single six-membered ring having four carbon atoms with nitrogen atoms in positions one and three
2 : a derivative of pyrimidine having its characteristic ring structure ; especially : a base (as cytosine, thymine, or uracil) that is a constituent of DNA or RNA