/ Dictionary / Index N naphthyl group: Meaning and Definition of Find definitions for: naph'thyl group" Pronunciation: [key] — Chem. Chem. Also calledthe univalent group CH–, having a replaceable hydrogen atom in the first, or alpha, position; 1-naphthyl group. Also calledthe univalent group CH–, having a replaceable hydrogen atom in the second, or beta, position; 2-naphthyl group. Also called Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. naphthyl napier Related Content Daily Word Quiz: banshee Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language