/ Dictionary / Index P posse: Meaning and Definition of Find definitions for: pos•se Pronunciation: (pos'ē), [key] — n. See a body or force armed with legal authority. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: posse (Thesaurus) poss. posse comitatus Related Content Daily Word Quiz: secular Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language