/ Dictionary / Index N nitroso group: Meaning and Definition of Find definitions for: nitro'so group" Pronunciation: [key] — Chem. Chem. the univalent group O=N–. Also called Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. nitrosobenzene nitrosourea Related Content Daily Word Quiz: feline Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language