10 U.S.C. § 8001 Definitions
(a) In this subtitle:(1) The term “Navy” means the United States Navy. It includes the Regular Navy, the Fleet Reserve, and the Navy Reserve. (2) The term “Marine Corps” means the United States Marine Corps. It includes the Regular Marine Corps, the Fleet Marine Corps Reserve, and the Marine Corps Reserve. (3) The term “member of the naval service” means a person appointed or enlisted in, or inducted or conscripted into, the Navy or the Marine Corps. (4) The term “enlisted member” means a member of the naval service serving in an enlisted grade or rating. It excludes, unless otherwise specified, a member who holds a permanent enlisted grade and a temporary appointment in a commissioned or warrant officer grade. (5) The term “officer” means a member of the naval service serving in a commissioned or warrant officer grade. It includes, unless otherwise specified, a member who holds a permanent enlisted grade and a temporary appointment in a commissioned or warrant officer grade. (6) The term “commissioned officer” means a member of the naval service serving in a grade above warrant officer, W–1. It includes, unless otherwise specified, a member who holds a permanent enlisted grade or the permanent grade of warrant officer, W–1, and a temporary appointment in a grade above warrant officer, W–1. (7) The term “warrant officer” means a member of the naval service serving in a warrant officer grade. It includes, unless otherwise specified, a member who holds a permanent enlisted grade and a temporary appointment in a warrant officer grade. (8) The term “officer restricted in the performance of duty” means an officer of the Navy designated for engineering duty, aeronautical engineering duty, special duty, or limited duty, or an officer of the Marine Corps designated for limited duty.
(b) For the purposes of this subtitle, a member of the naval service who holds a temporary appointment in a grade higher than his permanent grade is considered, unless otherwise specified, to be serving in the higher grade.