The word "protuberate" means to bulge or stick out prominently. Some synonyms for "more protuberate" could be "more prominent," "more projecting," "more pronounced," "more protruding," "more bulging," or "more swelling." These words all convey a similar meaning to "more protuberate" and can be used to describe objects that stick out or bulge more than others. For example, a person's veins can be described as "more prominent" when they are visible and bulging on the surface of the skin. Additionally, a plant with leaves that bulge outwards could be described as "more protruding" than other plants.