"Acclivitous" is a word in ENGLISH

Acclivous.

of Acclivity

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

Sloping upward; rising as a hillside; -- opposed to declivous.

Attended with great labor, like the ascending of acclivities; difficult; laborious; as, an arduous employment, task, or enterprise.

A steep acclivity, as the slope of a hill, or the side of a ravine.

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

A returning ascent or ascension; acclivity.

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