12 Pa. Code § 119.1
The following words and terms, when used in this chapter, have the following meanings, unless the context clearly indicates otherwise:
Act—Section 2501-C of The Administrative Code of 1929 (71 P. S. § 670.101).
Center—The Center for Local Government Services of the Department.
COG—This term shall be divided as follows:
(ii) Group B. Any two or more municipalities that are considering joining together formally to discuss, plan and act on matters of common concern.
Municipality—A city, borough, township or county.