5 C.F.R. § 831.1202
As used in this subpart-
Accommodation means an adjustment made to an employee's job or work environment that enables the employee to perform the duties of the position. Reasonable accommodation may include modifying the worksite; adjusting the work schedule; restructuring the job; obtaining or modifying equipment or devices; providing interpreters, readers, or personal assistants; and reassigning or retraining the employee.
Basic pay means the pay an employee receives that is subject to civil service retirement deductions. The definition is the same as the definition of "basic pay" under 5 U.S.C. 8331(3) .
Commuting area means the geographic area that usually constitutes one area for employment purposes. It includes a population center (or two or more neighboring ones) and the surrounding localities in which people live and can reasonably be expected to travel back and forth daily from home to work in their usual employment.
Disabled and disability mean unable or inability, because of disease or injury, to render useful and efficient service in the employee's current position, or in a vacant position in the same agency at the same grade or pay level for which the individual is qualified for reassignment.
Examination and reexamination mean an evaluation of evidentiary material related to the question of disability. Unless OPM exercises its choice of a physician, the cost of providing medical documentation rests with the employee or disability annuitant, who must provide any information OPM needs to make an evaluation.
Medical condition means a health impairment resulting from a disease or injury, including a psychiatric disease. This is the same definition of "medical condition" as in § 339.104 of this chapter.
Medical documentation and documentation of a medical condition mean a statement from a licensed physician or other appropriate practitioner that provides information OPM considers necessary to determine an individual's entitlement to benefits under this subpart. Such a statement must meet the criteria set forth in § 339.104 of this chapter.
Permanent position means an appointment without time limitation.
Physician and practitioner have the same meanings given in § 339.104 of this chapter.
Qualified for reassignment means able to meet the minimum requirements for the grade and series of the vacant position in question.
Same grade or pay level means, in regard to a vacant position within the same pay system as the employee currently occupies, the same grade and an equivalent amount of basic pay. A position under a different pay system or schedule is at the "same pay level" if the representative rate, as defined in § 532.401 of this chapter, equals the representative rate of the employee's current position.
Useful and efficient service means
Vacant position means an unoccupied position of the same grade or pay level and tenure for which the employee is qualified for reassignment that is located in the same commuting area and is serviced by the same appointing authority of the employing agency. The vacant position must be full time, unless the employee's current position is less than full time, in which case the vacant position must have a work schedule of no less time than that of the current position. In the case of an employee of the United States Postal Service, a vacant position does not include a position in a different craft or a position to which reassignment would be inconsistent with the terms of a collective bargaining agreement covering the employee.
5 C.F.R. §831.1202