De‐cliv″i‐ty (?), n.; pl.Declivities (#). [L. declivitas, fr. declivis sloping, downhill; de + clivus a slope, a hill; akin to clinare to incline: cf. F. déclivité. See Decline.] 1. Deviation from a horizontal line; gradual descent of surface; inclination downward; slope; — opposed to acclivity, or ascent; the same slope, considered as descending, being a declivity, which, considered as ascending, is an acclivity.
2. A descending surface; a sloping place.
Commodious declivities and channels for the passage of the waters. Derham.