Meaning of pyrazolone

py•raz•o•lone

Pronunciation: (pi-raz'u-lōn", pī-), [key]
— n. Chem.
  1. any of the group of heterocyclic compounds containing the pyrazoline ring in which one carbon atom is doubly linked to an oxygen atom not in the ring.
  2. the parent compound, CHNO.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.