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14 Secret Code Words You’re Not Meant to Know

Updated: Apr. 04, 2024

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

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10-33
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10-33

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. Here are 10 more emergency phrases you should know before you travel.

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Code 10
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Code 10

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 authorization 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 Walmart, however, Code 10 just means there’s a dry spill.

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7500
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7500

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 cockpit 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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Code Adam
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Code Adam

This is an alert for a missing child that’s used in many public locations like malls, hospitals, supermarkets, and museums. Walmart coined the term in 1994 in memory of Adam Walsh, a 6-year-old who was abducted from a Sears and was found murdered. In 2003, Congress mandated that all federal buildings use Code Adam procedures. We bet you never knew that these common company logos have hidden messages.

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Code Blue
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Code Blue

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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Code Bravo
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Code Bravo

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. Here find out the funny code names that the American military used seriously.

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Code Oscar
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Code Oscar

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. Check out these 9 hilarious military code names you won’t believe were actually used.

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Code Silver
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Code Silver

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
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Doctor Firestone

Dr. 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 Dr. Firestone to the fifth floor,” discreetly letting the staff know where the fire is without causing a panic. Some hospitals use Code Red to indicate a fire. Check out these surprising, often hilarious medical code words doctors and nurses use.

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Echo, Echo, Echo
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Echo, Echo, Echo

No, this isn’t someone listening to their voice resonate through a cave. This code means two ships are about to collide. Cruise ships may also use this code to alert everyone on board of high winds. ‘Bravo bravo ship‘ is another alerting code word on cruises that you should be aware of. Here are 75 funny words you’ve never heard before.

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Inspector Sands
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Inspector Sands

Transportation officials in the U.K. use this as a subtle code for a fire or bomb scare on railways and the London Underground network. After the Manchester Arena bombing, public announcements called for Inspector Sands to “please report to inspect and control.” Don’t miss these 12 hidden messages in everyday objects.

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Operation Rising Star
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Operation Rising Star

If you hear this phrase over the intercom while you’re flying, it means someone died on the plane. Operation Bright Star indicates a medical emergency on the flight.

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Pan-Pan
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Pan-Pan

Pan-Pan is an international radio signal that alerts others of a serious emergency on board a plane, boat, or other vehicle, but does not pose an immediate threat to the vehicle or the people on board. While someone may use Mayday when a plane is about to crash or there’s a fire on a ship, Pan-Pan could mean a boat has a slow leak or there’s a problem with a plane’s engine. Here are 11 more mysterious flight codes you always hear pilots say.

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Time Check
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Time Check

If you hear a time check announced over a loudspeaker in a store (it may sound like, “Time check, the time is 1:30″), there’s a bomb threat. Shoppers who know what this code phrase means should leave immediately, but store employees must reportedly try to locate the bomb when they hear a time check. We can only hope they get paid overtime for that. Next, find out the most clever Secret Service code names for U.S. presidents.