"Clivity" is a word in ENGLISH

A slope or inclination of the earth, as the side of a hill, considered as ascending, in opposition to declivity, …

The degree of elevation of an object, or the angle it makes with a horizontal line; inclination; rising grade; as, …

Deviation from a horizontal line; gradual descent of surface; inclination downward; slope; -- opposed to acclivity, or ascent; the same …

The rate of ascent or descent; gradient; deviation from a level surface to an inclined plane; -- usually stated as …

An inclined plane; an ascent o/ descent; a grade or gradient; a slope.

táklad - To ascend, climb, clamber, scale, go up-hill, march up an incline, slope, hill, etc. Táklad na kamó. Now, …

tolokádon - Ascent, slope, rise, incline, steep, acclivity, up-hill. (cf. tokád, takládon, takláron, tolokáron).