S.C. Code Ann. § 56-1-630

As used in this article: (1) "Party state" means a state, territory, or possession of the United States, the District of Columbia, or the Commonwealth of Puerto Rico. (2) "Home state" means the state which has issued and has the power to suspend or revoke the use of the license or permit to operate a motor vehicle. (3) "Conviction" means a conviction of any offense related to the use or operation of a motor vehicle which is prohibited by state law, municipal ordinance, or administrative regulation, or a forfeiture of bail, bond, or other security deposited to secure appearance by a person charged with having committed any of these offenses, and which conviction or forfeiture is required to be reported to the licensing authority. (4) "Licensing authority" for purposes of South Carolina shall mean the Department of Motor Vehicles.