When it comes to the airline industry, it seems like they’ve gone and created a language of their own. Filled with slang and acronyms, overhearing an airline employee will make you want to open up a translation app on your phone. And when they do decide on a word, the spelling may throw you for a loop. Is it, roundtrip, round trip, or round-trip? We’ve seen it every way possible. Also, for the record, it’s nonstop not non-stop or non stop, as non is a prefix.

Everyday Airline Lingo Explained

While the list of industry and insider jargon is extensive, I’ve taken some of the more popular and misunderstood terms into account to break down their meanings. While many you’ve heard before, you might find out that you’ve been misusing them all along. Here’s a rundown of some common phrases and idioms that every frequent flyer should be aware of.

Direct Flight

This is one of the most misunderstood words in the industry among flyers. A direct flight is not a nonstop flight. Commonly confused, a direct flight may contain a stop(s) along the way to the final destination to on or offload passengers. The key here is that a direct flight does not change its flight number despite touching down between two points. Therefore, it’s considered one continuous trip. Direct flights are less frequent nowadays with better fuel efficiency on most aircraft; however, a handful of airlines are still marketing flights as direct, especially Southwest.


An open-jaw itinerary or open-jaw flight is a roundtrip ticket in which the origin or destination airport is not the same in both directions. As an example, a roundtrip ticket on a fare from Atlanta (ATL) to Los Angeles (LAX) with the return portion from San Diego (SAN) to Atlanta (ATL). This itinerary would be considered an open-jaw as the ticket is arriving and departing from two different Californian airports. Open-jaws are generally booked so that a flyer can explore and travel between two destinations without having to backtrack to the arrival airport.


Pitch is the term used to define the legroom between two airline seats. Measured by the distance from the back of one airplane seat to the seat in front of it, seat pitch is generally measured in inches. On U.S. based airlines seat pitch can vary from a measly 28 to a generous 33 inches of pitch. To find out who offers the most real estate for your legs in economy, click here.

Related: Wild Pitch: US Airlines With the Most Legroom in Economy... and the Least


ETOPS is an acronym in the aviation industry for Extended Operations, or technically “extended-range twin-engine operational performance standards." So what does that actually mean? It is the range that airplanes may operate where there are no nearby airports or landing areas. ETOPS leveled certifications are administered to specific models of aircraft that allow them to service long-range routes with a buffer area and time frame to land safely in case of an engine failure. 


IFE is the acronym for In-Flight Entertainment. The term is mostly synonymous with the seat back video monitors on airplanes, but it also includes music channels, wi-fi, moving maps, and maybe even the Southwest flight attendant’s stand-up comedy routine you might be subjected to.


Probably the most well-known phrase on the list, a red-eye is a flight that departs at nighttime and is scheduled to arrive the following morning. Generally, flights are red-eyes when they travel from West to East and the time zone changes don’t allow for a full night’s rest. This leaves some passengers semi-exhausted with the namesake pair of puffy red-eyes.

Record Locator/PNR

Nope, a record locator isn’t a hipster looking for some vinyl at the nearby Goodwill. It’s the alphanumeric codes that are six characters long, created when an airline reservation is made. Often used in conjunction with a PNR (Passenger Name Record), these two terms are what the airlines use to store travelers’ itineraries, names, and flight information into their reservation databases. The codes often look like this: XT4D32, and are displayed on confirmation emails and usually on your boarding pass.

Fifth Freedom

Fifth Freedom refers to the airline right that allows a carrier to fly between two separate foreign countries, as long as the flight originates or terminates in the carrier’s home country. As an example, Emirates operates a flight from New York (JFK) to Dubai (DXB) that heads eastward with a brief stop in Milan (MXP). With fifth freedom rights, a passenger can fly only the New York to Milan segment of that service without the need to fly onward to Dubai. To find out a list of available fifth freedom flights and how they can benefit you, look here.

Related: What Are Fifth Freedom Flights?


Beyond being a Jerry Garcia fan, a deadhead in the aviation industry refers to an off-duty employee of an airline traveling in a passenger seat. Deadheading is commonly used for an airline to transport its crew to another city so they can be positioned for work assignment at another destination.


Not to be confused with deadheading, a non-rev (non-revenue) passenger is an airline employee or their certified friends and family flying on a deeply discounted airline ticket. These flights are generally on a standby basis and for personal travel needs, non-work-related. Non-rev tickets generate no income for the airline and are subject to availability.

Legacy Carrier

By definition, a legacy carrier is an airline with an established route network before the Airline Deregulation Act of 1978. But the term is more commonly used regarding a carrier that provides a higher quality of service than a low-cost carrier. However, the lines are blurring now as traditional legacy carriers mimic business models set out by rival budget companies. Delta, United, and American are often cited as the big three legacy carriers, but Alaska and Hawaiian also fall into the legacy category.


ULCC is the acronym for Ultra-Low-Cost-Carrier. ULCCs like Spirit, Allegiant, and Frontier Airlines rely on a business model that offer rock-bottom fare prices alongside a greater number of ancillaries and add-on fees. Often labeled no-frill airlines, ULCC's often reduce operating cost by flying the same model of aircraft, operate point-to-point routes, and are not members of any airline alliances. Ultra-low-cost-carriers generate non-flight revenue by imposing fees for seat selection, carry-on/checked baggage, and drinks/snacks onboard.

Related: The Best and Worst Low-Cost Airlines in Europe


A codeshare agreement or codesharing refers to a flight in which two or more airlines market and are able to sell tickets a specific flight operated by one carrier. Codeshares allow airlines to sell tickets that extend beyond their route networks in conjunction with their codeshare partner airline. For example, if a flyer based in Chicago (ORD) wanted to fly to Melbourne, Australia (MEL), where there are no nonstop flight options, they could take advantage of the codeshare agreement between American and Qantas and purchase an itinerary from American Airlines. That prevents travelers from having to buy two separate tickets on each airline. Codeshares are most prevalent amongst the three major worldwide airline alliances which you can learn more about here.


Metal is industry slang for which carrier's aircraft is operating the flight. For example, a nonstop flight from Boston (BOS) to Paris (CDG) can be purchased on the Delta website, and through a codeshare agreement will actually be flown on an Air France airplane. Therefore the flight is ticketed by Delta but flown on Air France "metal."


The abbreviation for Irregular Operations, IROP is industry-speak for when a flight schedule is disrupted. IROP includes flight delays and cancellations due to weather, "acts of God," aircraft service, equipment change, or for crew rest. Either way, if you happen to overhear IROP at the airport, odds are you’re not getting to your destination on time.

Layover vs. Stopover

Don’t get these two terms confused. Despite sounding the same, they have different meanings and your time could be at stake.

A layover is a flight connection ranging from as short as a half an hour upwards to 23 hours and 59 minutes. Anything under the 24-hour mark classifies as a layover. Layovers can last overnight, and depending on the booking site, building in an extended layover shouldn’t change your final flight price if kept under the 24-hour parameter.

A stopover refers to a connection that is over the 24-hour mark and can last multiple days (domestically a stopover is considered a connection of over four hours). Stopovers are generally found on routes that don’t have a daily frequency or if an airline's flight schedule allows for them. Stopovers can be an excellent tool for flyers to take some time to explore a city on the way to their final destination. Over the last few years, we have seen airlines relaxing their stopover policies and even promoting free stopovers to entice travelers to break up their journey using a multi-day stopover. To find out more about how to maximize a free stop on your next trip, click here.

Related: The 9 Easiest Airlines for Booking Free Stopovers

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