“allowable military service” means honorable active service of not more than 5 years in an armed force (including service in the National Guard when ordered to active duty for the United States Government), when the service is not creditable in computing another annuity.

“other prior allowable service” means civilian service as an officer or employee of the Government or District of Columbia government not covered by subsection (d)(1) of this section.

“congressional employee” has the same meaning given that term in section 2107 of title 5.