An alderman is a member of a municipal legislative body in a town or city with many jurisdictions. Members of Chicago's city council, for instance, use the title.
The title is Anglo-Saxon in origin, literally meaning "elder-man", and was used by the chief nobles presiding over shires.
See also: ealdorman
Members of higher branches of municipal or borough councils in England used the title prior to 1974. The title continues to be used in the Republic of Ireland, being used by the first person elected in a multi-seat local government ward.