/ Dictionary / Index P placentation: Meaning and Definition of Find definitions for: plac•en•ta•tion Pronunciation: (plas"un-tā'shun), [key] — n. the formation of a placenta. the manner of placement or construction of a placenta. the disposition or arrangement of a placenta or placentas. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: placentation (Thesaurus) placentate Placentia Related Content Daily Word Quiz: cur Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language