5 C.F.R. § 550.1103
For purposes of this subpart-
Agency means an executive department or agency; a military department; the United States Postal Service; the Postal Regulatory Commission; any nonappropriated fund instrumentality described in 5 U.S.C. 2105(c) ; the United States Senate; the United States House of Representatives; any court, court administrative office, or instrumentality in the judicial or legislative branches of the Government; or a Government corporation. If an agency under this definition is a component of an agency, the broader definition of agency may be used in applying the provisions of 5 U.S.C. 5514(b) (concerning the authority to prescribe regulations).
Creditor Agency means the agency to which the debt is owed, including a debt collection center when acting in behalf of a creditor agency in matters pertaining to the collection of a debt (as provided in § 550.1110 ) .
Debt means an amount owed to the United States from sources which include loans insured or guaranteed by the United States and all other amounts due the United States from fees, leases, rents, royalties, services, sales of real or personal property, overpayments, penalties, damages, interest, fines and forfeitures (except those arising under the Uniform Code of Military Justice), and all other similar sources.
Debt collection center means the Department of the Treasury or other Government agency or division designated by the Secretary of the Treasury with authority to collect debts on behalf of creditor agencies in accordance with 31 U.S.C. 3711(g) .
Disposable pay means that part of current basic pay, special pay, incentive pay, retired pay, retainer pay, or in the case of an employee not entitled to basic pay, other authorized pay remaining after the deduction of any amount required by law to be withheld (other than deductions to execute garnishment orders in accordance with parts 581 and 582 of this chapter). Among the legally required deductions that must be applied first to determine disposable pay are levies pursuant to the Internal Revenue Code (title 26, United States Code) and deductions described in § 581.105(b) through (f) of this chapter.
Employee means a current employee of an agency, including a current member of the Armed Forces or a Reserve of the Armed Forces (Reserves).
FCCS means the Federal Claims Collections Standards published in 31 CFR parts 900 through 904 .
Paying agency means the agency employing the individual and authorizing the payment of his or her current pay.
Salary offset means an administrative offset to collect a debt under 5 U.S.C. 5514 by deduction(s) at one or more officially established pay intervals from the current pay account of an employee without his or her consent.
Waiver means the cancellation, remission, forgiveness, or non-recovery of a debt allegedly owed by an employee to an agency as permitted or required by 5 U.S.C. 5584 , 10 U.S.C. 2774 , or 32 U.S.C. 716 , 5 U.S.C. 8346(b) , or any other law.
5 C.F.R. §550.1103