Steppest is a comparative adjective that is used to describe the degree of inclination or gradient of a surface or path. Synonyms for this word include steepest, sharpest, most precipitous, most vertical, and most sheer. These words all convey a similar sense of extreme slope, suggesting a rapid and potentially dangerous descent. Other possible synonyms for steppest might include words like plummeting, freefalling, plunging, or dropping. These words all convey a similar sense of downward motion and can be used to describe a variety of different scenarios, from a steeply angled ski slope to a treacherous mountain trail or a plunging waterfall.