Have you ever eavesdropped on an airline cabin crew, and wondered the meanings of their jargon? What does “cross-check” mean? Or "all-call"? And what about when they mention taking their “jump seats” during turbulence — are they preparing to strap on parachutes and jump out of the aircraft? The airline world has its own shoptalk and jargon, and listening passengers can discover an entirely new language.

We’ll let you in on some of the obscure terminology heard before and during a flight.

"Prepare doors for departure/arrival."

In an emergency situation, evacuation slides — which stow in a housing at the bottom of each aircraft door — are designed to automatically deploy with a blast of compressed carbon dioxide and nitrogen in just six seconds flat. But they won’t work if a crew member hasn’t “armed" the door: that is, pushed a lever on the door that connects the slide to the sill. Doors must be prepared, or armed, before a plane leaves, and disarmed upon arrival.

Depending upon the make and model of aircraft, this can mean lowering or raising a lever with one hand, or physically bending over and securing a bar to the floor latches. Some older aircraft require a strap to be placed across the cabin door’s windows, so employees greeting the aircraft from the jet bridge know whether the slide is engaged or not. Door safety is imperative: unsuspecting gate agents could accidentally open an armed door and have a slide pop out onto them and into the bridge.

"Cross-check" and "cross-check complete."

After flight attendants prepare for arrival or departure, the aircraft’s doors need to be cross-checked — airline-speak for double-checked by another flight attendant. Sometimes you will hear, “Doors are armed and cross-check complete” which verifies the doors are engaged and ready for an evacuation in the event of an emergency. Some airlines' cross-checks are said over the PA and others are verified via the private intercom.

"All-call."

Airlines have different procedures for flight attendants to verify their cross-checks. Sometimes it's done over the PA system; other times it's requested privately. There's where phrases such as "standby for all-call" come in. This means the inflight crew calls in from their assigned positions via the telephone intercom, conference-style.

"Jump seat."

This term refers to the small seats flight attendants take during takeoff, landing, and turbulence. When he or she stands up, the seat automatically closes, or “jumps."

"Bulkhead."

The bulkhead is the dividing wall on an aircraft, usually found ahead of the first row one. It separates the cabin seating from the galley or lavatory. (Some passengers appreciate these rows due to the extra legroom.)

"Extender."

Passengers must have seat belts fastened before the aircraft is pushed back from the gate for departure. But what about larger passengers who cannot connect the buckle and the tongue of a standard lap belt? They receive a seatbelt extension — “extender” for short — which augments belt length by about 25 inches.

"Spinner."

Passengers who arrive at the last moment and don’t have a seat assignment are occasionally told by a gate agent to board the aircraft and find an empty seat. This can result in a flustered passenger standing in the aisle, spinning as they search. You may hear a flight attendant call their cohort on the intercom or announce over the PA to a crew member, “We have a spinner mid-cabin. Are there any seats in the back?”

"Demo."

While demo is usually short for demonstration, flight attendants use the term to refer to the pre-flight passenger safety briefing. Fun fact: Flight attendants use a seatbelt extender during the demo to illustrate the act of fastening and unfastening their seatbelts.

"Deadhead."

Jerry Garcia fans need not get excited. Deadhead is the term for a crew member who is on duty, but flying as a passenger, heading home after a flight or to another airport to catch one. If a crew member calls out sick, the airline’s crew scheduling system will “deadhead” a pilot or flight attendant to the city to replace the absent employee.

"Redeye."

This unpleasant term refers to an overnight flight. For crew-members, they are the graveyard shift of the air. While staying up all night can be tedious for new flight attendants who are not used to it, these routes can also mean easy service and plenty of time for galley gossip since most passengers sleep.

"Equipment."

For some unknown reason, an aircraft in the airline industry is called "equipment." “Equipment looks good" means the plane has no issues or mechanical problems. On the other hand, “We are delayed because we need an equipment swap" is often met with groans.

"Runners."

"We’re waiting for runners" means "we have passengers coming from another flight that was late." Read: they are likely sprinting through the airport. If flight attendants use this term with each other, it means they need to get the passengers’ bags stowed and the people seated as fast as possible so they can depart on time. Note: Some airlines will hold for runners. Others aren’t so kind.

BONUS:

The chimes.

Passengers can try and guess the meaning of those various chimes heard when flying, but we should warn you that the number of “dings” means different things on different airlines. Sometimes the chimes mean the plane is going above or below 10,000 feet. Other times it’s a warning of choppy air ahead.

The call button.

Other times, that “ding” means a call button’s been pressed. Some flight attendants call this an abuse button, especially when passengers overuse their authority by acting as if they are the only person on board. Call buttons are acceptable to use when passengers truly need something, like help with a drink spill, or they feel sick and need assistance. Call button etiquette dictates passengers to wait until everyone else has been served before requesting seconds. Warning: Parents can expect to get the stink-eye if they allow their toddler to use the call button as a musical toy.

That mysterious flight attendant telephone.

As for the secret chatter the flight attendants have on the intercom with the pilots and each other, that also varies, covering topics like coffee, bathroom breaks, wheelchairs, delays, cabin temperature, weather — sometimes even sports scores that could be shared with Wi-Fi-less passengers.

Beth Blair is a former flight attendant and a freelance writer.

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