In Japan, the classic Mega Man character is known as Rockman.
Capcom released the original game as Rockman in Japan in 1987. The protagonist’s original name is Rock, paired with his sister robot Roll, creating a musical “rock and roll” naming theme. When Capcom localized the game for North America, it changed the character’s name to Mega Man, which became the standard English name for the classic hero.
Rockman is more than a translated nickname: it is the established Japanese title for the classic Mega Man series and its main character. The name can also appear in related Japanese titles, such as Rockman X and Rockman.EXE, although those series feature different versions of the hero or different fictional settings. Proto Man, Bass, and Blues are not alternate names for the original character; Blues is the Japanese name associated with Proto Man.