or grade·a·bil·i·ty

[ grey-duh-bil-i-tee ]
/ ˌgreɪ dəˈbɪl ɪ ti /

noun Transportation.

a measure of a truck's pulling power expressed as the steepest grade the truck can climb with a full load.
Compare grade(def 9).

Origin of gradability

First recorded in 1950–55; grade + -ability Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019