German Meaning: The name Wilbur is a German baby name. In German the meaning of the name Wilbur is: Resolute or brilliant. American Meaning: The name Wilbur is an American baby name. In American the meaning of the name Wilbur is: Resolute or brilliant.he name Wilbur is a German baby name. In German the meaning of the name Wilbur is: Resolute or brilliant. American Meaning: The name Wilbur is an American baby name.