/ Dictionary / Index M macroplankton: Meaning and Definition of Find definitions for: mac•ro•plank•ton Pronunciation: (mak"rō-plangk'tun), [key] — n. planktonic organisms of about 1 mm in length. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. macrophyte macropodous Related Content Daily Word Quiz: philanthropy Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language