/ Dictionary / Index M macromolecule: Meaning and Definition of Find definitions for: mac•ro•mol•e•cule Pronunciation: (mak"ru-mol'u-kyl"), [key] — n. Chem. a very large molecule, as a colloidal particle, protein, or esp. a polymer, composed of hundreds or thousands of atoms. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: macromolecule (Thesaurus) macromineral macromutant Related Content Daily Word Quiz: inutiae Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language