/ Dictionary / Index P planospore: Meaning and Definition of Find definitions for: plan•o•spore Pronunciation: (plan'u-spôr", -spōr"), [key] — n. Biol. a zoospore. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. planometer plan position indicator Related Content Daily Word Quiz: simian Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language