/ Dictionary / Index P posterior pituitary: Meaning and Definition of Find definitions for: poste'rior pitu'itary. Pronunciation: [key] See under Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. posteriority posterity 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