Pyr"rol (?), n. [Gr. flame-colored (from fire) + L. oleum oil.] Chem.
A nitrogenous base found in coal tar, bone oil, and other distillates of organic substances, and also produced synthetically as a colorless liquid, C4H5N, having on odor like that of chloroform. It is the nucleus and origin of a large number of derivatives. So called because it colors a splinter of wood moistened with hydrochloric acid a deep red.
© Webster 1913.