"Gun bulge" refers to the visible impression or outline of a gun carried by an individual. Synonyms for this term could include "weapon protrusion," "gun print," "firearm outline," or "concealed carry imprint." Other possible synonyms could be "holster bulge," "gun impression," or "gun shape." In the context of law enforcement or security work, "weapon visibility" or "gun exposure" may also be appropriate alternatives. Regardless of the specific term used, all of these synonyms convey the same basic idea of a visible indication that someone is carrying a gun, either openly or concealed.