/ Dictionary / Index P polyclad: Meaning and Definition of Find definitions for: pol•y•clad Pronunciation: (pol'ē-klad"), [key] — n. any free-swimming, marine flatworm of the order Polycladida, having a broad, flat body and a many-branched gastrovascular cavity. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. polycistronic polyclinic Related Content Daily Word Quiz: cygnet Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language