14 C.F.R. § 234.2
For the purpose of this part:
Cancelled flight means a flight operation that was not operated, but was listed in a carrier's computer reservation system within seven calendar days of the scheduled departure.
Discontinued flight means a flight dropped from a carrier's computer reservation system more than seven calendar days before its scheduled departure.
Diverted flight means a flight which is operated from the scheduled origin point to a point other than the scheduled destination point in the carrier's published schedule. For example, a carrier has a published schedule for a flight from A to B to C. If the carrier were to actually fly an A to C operation, the A to B segment is a diverted flight, and the B to C segment is a cancelled flight.
Extra-section flight means a flight conducted as an integral part of scheduled passenger service, that has not been provided for in published schedules and is required for transportation of traffic that cannot be accommodated on the regularly scheduled flight.
Flight means any nonstop scheduled passenger flight segment with a specific flight number scheduled to be operated pursuant to a published schedule within a specific origin-destination city pair, other than transborder or foreign air transportation. In the case of reporting to computer reservations system vendors, flight also means one-stop or multi-stop single plane scheduled operations that include any flight segments for which performance is reported pursuant to this part.
Late or late flight means a flight that arrives at the gate 15 minutes or more after its published arrival time.
Mishandled-baggage report means a report filed with a carrier by or on behalf of a passenger that claims loss, delay, damage or pilferage of baggage.
Mishandled checked bag means a checked bag that is lost, delayed, damaged or pilfered, as reported to a carrier by or on behalf of a passenger.
New flight means a flight added to a carrier's schedule to operate in a specific origin-destination city pair and not scheduled to depart within 30 minutes of any discontinued flight that was contained in the carrier's published schedules for the same city pair during the previous month.
On-time means a flight that arrives less than 15 mintues after its published arrival time.
On-time performance means the percentage of scheduled operations of a specific flight that an air carrier operates on-time during a month.
On-time performance code means a single character determined in accordance with the provisions of this part that reflects the monthly on-time performance of certain nonstop flights and single plane one-stop or multi-stop flights, the schedule and availability of which are listed in a computer reservation system (CRS) regulated by 14 CFR part 255 .
Reportable flight.
Reporting carrier.
14 C.F.R. §234.2