Protuberances are defined as bulges or protrusions on a surface. Synonyms for this word include prominences, bumps, lumps, knobs, and protrusions. These words all refer to a physical irregularity on a surface that can be seen or felt. Other synonyms for protuberances may include humps, ridges, tumescences, or swellings. Depending on the context, different synonyms may be more fitting to describe the specific type of protuberance that is being referred to. For example, knobs may refer to a small, rounded protuberance, while humps may refer to a larger, more irregular bulge. Overall, there are many different synonyms that can be used to describe protuberances.