/ Dictionary / Index P polyestrous: Meaning and Definition of Find definitions for: pol•y•es•trous Pronunciation: (pol"ē-es'trus), [key] — adj. having several estrus cycles annually or during a breeding season. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: polyestrous (Thesaurus) polyester polyether Related Content Daily Word Quiz: paradox Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language