1) a clause in a statute or zoning ordinance (particularly a city ordinance) which permits the operator of a business or a land owner to be exempt from restrictions on use if the business or property continues to be used as it was when the law was adopted. upon passage of the statute or regulation, the specific property may be referred to as “grandfathered in.” example: the city passes an ordinance which does not permit retail businesses in a particular zone, but any existing store can continue to function in the area, even with new owners. however, if the premises stop being a retail outlet then the grandfather clause will lapse. 2) among the state constitutional amendments passed by southern states in the late 1800s to keep blacks from voting, “grandfather clauses” denied voter registration to people who were illiterate, who did not own property or could not pass a test on citizenship obligations, unless their grandfathers had served in the confederate army. such laws are now unconstitutional.