14 CFR 257.3 - Definitions.
As used in this part:
(a) Air transportation means foreign air transportation or interstate air transportation as defined in 49 U.S.C. 40102 (a)(23) and (25) respectively.
(b) Carrier means any air carrier or foreign air carrier as defined in 49 U.S.C. 40102(2) or 49 U.S.C. 40102(21), respectively, that is engaged directly in scheduled passenger air transportation, including by wet lease.
(c) Code-sharing arrangement means an arrangement whereby a carrier's designator code is used to identify a flight operated by another carrier.
(d) Designator code means the airline designations originally allotted and administered pursuant to Agreements CAB 24606 and 26056.
(e) Long-term wet lease means a lease by which the lessor provides both an aircraft and crew dedicated to a particular route(s), and which either:
(1) Lasts more than 60 days; or
(2) Is part of a series of such leases that amounts to a continuing arrangement lasting more than 60 days.
(f) Ticket agent has the meaning ascribed to it in 49 U.S.C. 40102(40).
(g) Transporting carrier means the carrier that is operating the aircraft in a code-sharing arrangement or long-term wet lease.