In this subtitle, the following terms have the meanings indicated. Terms Defined. “Administrative law judge” has the meaning stated in COMAR 28.02.01. “Contested case” has the meaning stated in State Government Article, §10-202, Annotated Code of Maryland. “Filed” means, unless otherwise indicated in this chapter, when the document is: Received by the Secretary or, if earlier, postmarked; and If required, served on the other parties to the proceeding. “Hearing” means a hearing to determine a contested case. “Party” means a person or agency, including the Department, named or admitted to participate in a hearing. “Person” includes a governmental entity or an instrumentality or unit of a governmental entity.