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Glossary for the airline industry

From A-Z, this glossary covers definitions and explanations for common airline industry terminology.

match criteria

Portion of a query coded to find fares and use that fare amount.

maximum permitted mileage

The maximum number of miles that may be traveled for a fare component without incurring a mileage surcharge.

merchandise services

An optional service that is not associated to any passenger travel or ticket. Such a service may be priced regardless of whether the customer is holding a passenger ticket. For example, a carrier might offer logo T-shirts for sale, whether or not a ticket exists.

merchandising

A key component of offer presentation, merchandising consists of product attributes used for selecting and filtering displayed offers so consumers can understand the details of the airline product.

MIBA

Multilateral Interline Travel Business Agreement for airline company business travel.

Mileage currency

Currency code XXX used to file mileage awards

mileage-based fares

A fare that is not governed by a designated routing map, but instead by a maximum permitted mileage (MPM) restriction.

min/max pricing

A type of continuous pricing where airlines distribute a minimum/maximum price range, eliminating the need to pre-distribute individual prices

minor subcategory

One of four qualifying subcategories of Category 10 (106-109) that states restrictions on combination types.

mirror image

(Subcategory 102, International fares) A round-trip pricing unit consisting of two fare components, half of a round trip (Tag 2 fare) using the same tariff, carrier, rule, and fare class code on both components, and where no differing mileage and/or HIP surcharges exist on the pricing unit.

MITA

Multilateral Interline Traffic Agreements Manual 

ML

Machine learning.

modify fares

A function that allows fares to be amended or canceled within a fares batch.

most significant carrier
  1. The carrier whose baggage rules will apply on journeys.
  2. For journeys that are required to follow DOT reservations, it is the first most significant marketing carrier on the journey, as determined by these conditions, and charges for these journeys are applied per direction:
    a. For travel between two or more Tariff Conference areas, the carrier performing carriage on the first sector on the passenger's journey that crosses from one area to another. Exception: TC123 only, the carrier providing carriage on the first sector on the passenger's journey that crosses between TC1 and TC2.
    b. For travel between Tariff Conference sub-areas, the carrier performing carriage on the first sector on the passenger's journey that crosses from one sub-area to another.
    c. For travel within a Tariff Conference sub-area, the carrier performing carriage on the first international sector on the passenger's journey.
  3. For all other journeys, it is the most significant operating carrier for each checked portion, and charges for these journeys are applied per checked portion:
    a. For travel between two or more Tariff Conference areas, the carrier performing carriage on the first sector on the checked portion that crosses from one area to another. Exception: TC123 only, the carrier providing carriage on the first sector on the checked portion that crosses between TC1 and TC2.
    b. For travel between Tariff Conference sub-areas, the carrier performing carriage on the first sector on the checked portion that crosses from one sub-area to another.
    c. For travel within a Tariff Conference sub-area, the carrier performing carriage on the first international sector on the checked portion.
    d. For travel within a single country, the first carrier on the checked portion.
MPM

Maximum permitted mileage.

multi-stop

A service of transportation with a single flight number making two or more intermediate stops.

multilateral fare agreement

An agreement between three or more trading partners to either send data or process data in a specified manner.

national

A person who has citizenship of a given country, either by birth or naturalization. Also called citizen.

NDC

New Distribution Capability.

NDC Exchange

An industry-owned solution that serves as a neutral hub to connect airlines with sellers, while performing real-time message translation that supports many industry standards and versions.