declivous

or de·cli·vent

[ dih-klahy-vuh s ]
/ dɪˈklaɪ vəs /

adjective

sloping downward.

Origin of declivous

1675–85; < Latin dēclīv(is) (see declivity) + -ous
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019