/ Dictionary / Index P progestin: Meaning and Definition of Find definitions for: pro•ges•tin Pronunciation: (prō-jes'tin), [key] — n. Pharm. any substance having progesteronelike activity. Also called Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: progestin (Thesaurus) progesterone progestogen 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