More protrusive refers to something that is sticking out or projecting further than something else. The antonyms for this word could be any word or phrase that represents the opposite of protrusion. Some possible antonyms for more protrusive include recessed, sunken, indented, concave, hollow, and depressed. Each of these words suggests a surface or area that is sunken or curved inward, rather than bulging or sticking out. Antonyms for more protrusive may also include words that describe a flat or even surface, such as level, smooth, or uniform. These words imply an absence of protrusion or unevenness.