/ Dictionary / Index D declivitous: Meaning and Definition of Find definitions for: de•cliv•i•tous Pronunciation: (di-kliv'i-tus), [key] — adj. having a somewhat steep downward slope. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: declivitous (Thesaurus) declive declivity Related Content Daily Word Quiz: gregarious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language