from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A five-membered heterocyclic ring compound, C4H5N, having an odor similar to chloroform, that is the parent compound of protoporphyrin.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. Any of a class of aromatic heterocyclic compounds containing a ring of four carbon atoms and a nitrogen atom; especially the simplest one, C4H5N.
Greek purros, red (from pūr, fire; see pyre) + -ole.(American Heritage® Dictionary of the English Language, Fourth Edition)
pyrrhós, red (Wiktionary)