/ Dictionary / Index C closed chain: Meaning and Definition of Find definitions for: closed' chain' Pronunciation: [key] — Chem. Chem. three or more atoms linked together to form a ring or cycle and represented accordingly by its structural formula. Cf. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. closed-captioned closed circuit Related Content Daily Word Quiz: lyre Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language