(i) Employer or Agency means any civil agency or instrumentality of the United States Government, or any other organization, group or institution employing an individual defined as an employee by this section. These terms also refer to officers and employees of an employer having responsibility for the supervision, direction or control of employees of that employer as an immediate superior, and to other employees designated by the employer to carry out the functions vested in the employer under the FECA and this part, including officers or employees delegated responsibility by an employer for authorizing medical treatment for injured employees.
20 CFR § 10.5
Certain words and phrases found in this part are defined in this section or in the FECA. Some other words and phrases that are used only in limited situations are defined in the later subparts of the regulations in this subchapter.