The term 'Namban' means red peppers in Japanese, but Curry namban came from 'namba,' which indicates a long green onion (similar to 'Kamo namban' or noodles with slices of duck in the broth, and 'Kashiwa namban' or noodles with pieces of chicken in broth).
カレー南蛮の「南蛮」は唐辛子のことではなく「なんば」が転じたもので、ネギ（長ネギ）のことを指す（「鴨南蛮」「かしわ南蛮」に同じ）。