In this subtitle, the following terms have the meanings indicated. Terms Defined. “Commission” means the Public Service Commission of Maryland. “Customer” means a person, partnership, association, corporation, or governmental agency being provided with water service by a utility. “Main” means a water pipe, owned, operated, or maintained by a water company, which is used for the transmission or distribution of water, but does not include “service pipe.” “Meter”, without other qualification, means a device or instrument which is used by a utility in measuring a quantity of water for billing purposes. “Premises” means a tract of land or real estate, including buildings and other appurtenances on it. “Service pipe” means the pipe which runs from the main to the customer's premises. “Utility” means a “water company” as defined in Public Utilities Article, §1-101, Annotated Code of Maryland. “Water plant” means plant and property owned by a water utility, used in its business operations of providing water service to its customers.