5 C.F.R. § 846.102
In this part-
CSRS means subchapter III of chapter 83 of title 5, United States Code.
CSRS/SS service means service subject to both CSRS deductions (or deductions under another retirement system for Federal employees if such service is creditable under CSRS) and social security deductions as a result of the Social Security Amendments of 1983. For this purpose, the service of an individual is considered CSRS/SS service if the service would have been covered under CSRS except for an election under section 208(a)(1)(A) of the Federal Employees Retirement Contribution Temporary Adjustment Act of 1983 to have no CSRS coverage.
Employee means an employee as defined by § 842.102 of this chapter.
Employing office means the office of an agency to which jurisdiction and responsibility for retirement matters for an employee have been delegated.
FERS means the Federal Employees Retirement System as described in chapter 84 of title 5, United States Code.
Former spouse means a former spouse as defined in § 838.103 or § 838.1003 of this chapter.
Member means a Member of Congress as defined in section 2106 f title 5, United States Code.
OPM means the Office of Personnel Management.
Qualifying court order means a court order acceptable for processing as defined in § 838.103 of this chapter or a qualifying court order as defined in § 838.1003 of this chapter.
Social security means coverage under the Old Age, Survivors, and Disability Insurance programs of the Social Security Act.
5 C.F.R. §846.102