A toxic colorless flammable liquid organic base with a disagreeable odor

• Usually derived from coal

Wiktionary Word definitions in Wiktionary
n. (context organic compound English) Any of a class of aromatic heterocyclic compounds containing a ring of five carbon atoms and an nitrogen atom; especially the simplest one, C 5 H 5 N.

WordNet Word definitions in WordNet
n. a toxic colorless flammable liquid organic base with a disagreeable odor; usually derived from coal

Wikipedia Word definitions in Wikipedia
Pyridine is a basic heterocyclic organic compound with the chemical formula C H N . It is structurally related to benzene , with one methine group (=CH−) replaced by a nitrogen atom. The pyridine ring occurs in many important compounds, including azines ...

The Collaborative International Dictionary Word definitions in The Collaborative International Dictionary
Pyridine \Pyr"i*dine\, n. [From Gr. ? fire.] (Physiol. Chem.) A nitrogenous base, C5H5N , obtained from the distillation of bone oil or coal tar, and by the decomposition of certain alkaloids, as a colorless liquid with a peculiar pungent odor. It is the ...