5 C.F.R. § 535.102
Agency has the meaning given that term in 5 U.S.C. 5102 .
Critical position means a position for which OPM has granted authority to the head of an agency to exercise the pay-setting authority provided in 5 U.S.C. 5377 .
Critical position pay authority means the authority that may be granted to the head of an agency by OPM under 5 U.S.C. 5377 to set the rate of basic pay for a given critical position under the provisions of that section.
Critical position pay rate means the specific rate of pay established by the head of an agency for an employee in a critical position based upon the exercise of the critical position pay authority. A critical position pay rate is a rate of basic pay to the extent provided in § 535.106 .
Employee means an employee (as defined in 5 U.S.C. 2105 ) in or under an agency.
Head of an agency means the agency head or an official who has been delegated the authority to act for the agency head in the matter concerned.
5 C.F.R. §535.102