/ Dictionary / Index P past mistress: Meaning and Definition of Find definitions for: past' mis'tress Pronunciation: [key] a woman who is thoroughly experienced or exceptionally skilled in a profession, art, etc. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. past master pastness Related Content Daily Word Quiz: hale Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language