The spelling of the word "steppest" may seem confusing at first. But if we break it down phonetically, it becomes clearer. The first syllable, "step," is pronounced like "stehp" (IPA: /stɛp/). The second syllable, "-pest," is pronounced like "pest" (IPA: /pɛst/). When we put the two syllables together, we get "stehp-pɛst," which becomes "steppest" (IPA: /ˈstɛp.ɛst/). This word is used to describe the steepest or most extreme slope or incline.