/ Dictionary / Index P pyrazoline: Meaning and Definition of Find definitions for: py•raz•o•line Pronunciation: (pi-raz'u-lēn", -lin, pī-), [key] — n. Chem. any of the group of heterocyclic compounds containing three carbon atoms, two adjacent nitrogen atoms, and one double bond in the ring. the parent compound, CHN. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. pyrazole pyrazolone Related Content Daily Word Quiz: fervor Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language