The persons who contributed to the Meiji restoration significantly were called genkun, and it is said that this term was an abbreviation created mainly by mass media, because they virtually led the politics in the new Meiji government for a long period (Choro-genkun (senior Genkun) -> Genkun-ro (old Genkun) -> Genro, or an abbreviation of Genkun-shoro (senior Genkun persons).
明治維新に功績のあった人物を元勲と呼ぶが、彼らが明治新政府において長期間に渡って事実上政治を牽引していたことから、主にマスコミ周辺から誕生した略称だと言われている（長老元勲→元勲老→元老、もしくは元勲諸老の略）。