/ Dictionary / Index D degree-day: Meaning and Definition of Find definitions for: de•gree-day Pronunciation: (di-grē'dā"), [key] — n. Engin. one degree of departure, on a single day, of the daily mean temperature from a given standard temperature. Abbr.: dd Cf. cooling degree-day, growing degree-day, heating degree-day. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: degree-day (Thesaurus) degree degree mill Related Content Daily Word Quiz: jaundice Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language