Something that bulges out or is protuberant or projects from its surroundings. Synonyms: bulge, bump, extrusion, gibbosity, gibbousness, hump, jut, prominence, protrusion, protuberance, swelling. "The hump of a camel" , "He stood on the rocky prominence" , "The occipital protuberance was well developed" , "The bony excrescence between its horns"