(organic chemistry) Any of a class of aromaticheterocycliccompounds containing a ring of four carbon atoms and a nitrogen atom; especially the simplest one, C4H5N. [from 19th c.]
“When cinchonine is distilled with solid potassium hydrate, it yields pyrrol and bases of both the pyridine and quinoline series.”
“Previous phases of the Phenix Project have included construction of a new plant in 1997 to manufacture high performance Diketo Pyrolo Pyrrol pigments.”