/ Dictionary / Index D diestrus: Meaning and Definition of Find definitions for: di•es•trus Pronunciation: (dī-es'trus), [key] — n. (in female mammals) an interval of sexual inactivity between periods of estrus. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: diestrus (Thesaurus) diestock diet Related Content Daily Word Quiz: feline Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language