14 secret code words you’re not meant to know (2024)

These phrases are meant to sound like random letters and numbers, but in certain situations they can be signs of a serious emergency. How many have you heard of?

Chances are, you’ve heard of the police code 10-4, which means “affirmative” or an acknowledgment of a message. But if you hear a police officer say 10-33, there’s a police emergency underway. However, the meaning of various “10 codes” (10-1, 10-2, 10-3, etc.) differ between police departments.

This phrase can mean a few different things. Hospitals can use it to signal a serious threat or mass casualties. If a store cashier issues a Code 10 authorisation request while you’re checking out, it means that she’s suspicious of you or your card. She’ll call your credit card company and answer a series of yes/no questions to evaluate the situation and call the authorities if need be. If you’re in a certain department stores, however, Code 10 just means there’s a dry spill in one of the aisles.

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You never want your pilot to say or signal this number. It means the plane has been hijacked. Because the meaning of this code has become pretty widespread, many airlines have installed a button or other device in the co*ckpit that silently switches the plane’s transponder to 7500, ABC News reports. Air traffic control will then ask the pilot to confirm he sent the 7500 code on purpose. The code 7700 is a general emergency signal for aircraft.

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This is an alert for a missing child that’s used in many public locations like malls, hospitals, supermarkets and museums. The US store chain Walmart coined the term in 1994 in memory of Adam Walsh, a six-year-old who was abducted from a Sears and was found murdered. In 2003, US Congress mandated that all federal buildings use Code Adam procedures.

Like police codes, not all hospitals use the same emergency codes, but generally, Code Blue means someone has gone into cardiac arrest.

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When airport security issues a Code Bravo, that means there’s a bomb threat or other security breach. Officials may actually yell it at people in the airport to scare them and make them freeze in their tracks so they can find the real threat faster.

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If you thought this had something to do with the Academy Awards, you are sadly mistaken. This code is used on ships to indicate a man overboard.

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Hospitals around the country use Code Silver as the code for a person in the building with a weapon, a hostage situation, or another violent situation that requires a lockdown. Either way, it isn’t something you want to hear in the hospital, regardless of whether you’re a doctor or patient.

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Doctor Firestone isn’t a real doctor, but you could hear the name in a real medical emergency. It lets hospital staff know there’s a fire in the building. The announcement would sound like, “Paging Doctor Firestone to the fifth floor,” discreetly letting the staff know where the fire is without causing a panic. Some hospitals also use Code Red to indicate a fire.

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