/ Dictionary / Index B branched chain: Meaning and Definition of Find definitions for: branched' chain' Pronunciation: [key] — Chem. Chem. an open chain of atoms, usually carbon, with one or more side chains attached to it. Cf. straight chain. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. branch cut branched polyethylene Related Content Daily Word Quiz: secular Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language