/ Dictionary / Index P Pu: Meaning and Definition of Find definitions for: Pu Pronunciation: [key] — Symbol, Chem. plutonium. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: pu (Thesaurus) ptyalism pub Related Content Daily Word Quiz: immense Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language