The military is full of interesting lingo. The Navy, Marine Corps, Air Force, and Army all have their own unique phrases. Some of these are so good, the civilian world just can’t resist picking them up when it hears them. Here are 17 phrases that jumped from the military ranks to the civilian sphere.

1. “Balls to the walls” (also, “Going balls out”)

Meaning: To go as fast as one possibly can.

From military aviation where pilots would need to get their aircraft flying as fast as possible. Their control levers had balls on the end. Pushing the accelerator all the way out (“balls out”), would put the ball of the lever against the firewall in the cockpit (“balls to the wall”). When a pilot really needed to zoom away, they’d also push the control stick all the way forward, sending it into a dive. Obviously, this would put the ball of the control stick all the way out from the pilot and against the firewall.

2. “Bite the bullet”

Meaning: To endure pain or discomfort without crying out

Fighters on both sides of the American Civil War used the term “bite the bullet,” but it appears they may have stolen it from the British. British Army Capt. Francis Grose published the book, “Dictionary of the Vulgar Tongue” in 1811 and used “chew the bullet” to explain how proud soldiers stayed silent while being whipped.

3. “Boots on the ground”

Meaning: Ground troops engaged in an operation

Credited to Army Gen. Volney Warner, “boots on the ground” is used to mean troops in a combat area or potential combat area. After the invasions of Iraq and Afghanistan, the term saw wide use and has ceased to refer exclusively to military operations. It can now be used to refer to any persons sent out to walk the ground in an area. It’s been employed in reference to police officers as well as political canvassers.

4. “Bought the farm”

Meaning: To die

Thought to date back to 1950s jet pilots, the phrase quickly spread to civilian circles. There is no clear agreement on exactly how the phrase came about. It could be from war widows being able to pay off the family farm with life insurance payments, or farmers paying off their farms with the damage payout they’d receive when a pilot crashed on their land, or the pilots who wanted to buy a farm after they retired being said to “buy the farm early” when they died.

5. “Caught a lot of flak”

Meaning: To be criticized, especially harshly

Flak is actually an acronym for German air defense cannons. The Germans called the guns Fliegerabwehrkanonen. Flieger means flyer, abwehr means defense, and kanonen means cannon. Airmen in World War II would have to fly through dangerous clouds of shrapnel created by flak. The phrase progressed in meaning until it became equated with abusive criticism.

6. “FUBAR”/”SNAFU”/”TARFU”

Meaning: Everything about the current situation sucks

All three words are acronyms. FUBAR stands for “F*cked up beyond all recognition,” SNAFU is “Situation normal, all f*cked up,” and TARFU is “Things are really f*cked up.” FUBAR and SNAFU have made it into the civilian lexicon, though the F-word in each is often changed to “fouled” to keep from offending listeners. The Army actually used SNAFU for the name of a cartoon character in World War II propaganda and instructional videos. Pvt. Snafu and his brothers Tarfu and Fubar were voiced by Mel Blanc of Bugs Bunny and Porky the Pig fame.

7. Geronimo

Usage: Yelled when jumping off of something

“Geronimo” is yelled by jumpers leaping from a great height, but it has military origins. Paratroopers with the original test platoon at Fort Benning, Georgia yelled the name of the famous Native American chief on their first mass jump. The exclamation became part of airborne culture and the battalion adopted it as their motto.

8. “Got your six”

Meaning: Watching your back

Military members commonly describe direction using the hours of a clock. Whichever direction the vehicle, unit, or individual is moving is the 12 o’clock position, so the six o’clock position is to the rear. “Got your six” and the related “watch your six” come from service members telling each other that their rear is covered or that they need to watch out for an enemy attacking from behind.

9. “In the trenches”

Meaning: Stuck in a drawn out, tough fight.

Troops defending a position will dig trenches to use as cover during an enemy attack, reducing the chance they’ll be injured by shrapnel or enemy rounds. In World War I, most of the war occurred along a series of trenches that would flip ownership as one army attacked another. So, someone engaged in fierce fighting, even metaphorical fighting, is “in the trenches.”

10. “No man’s land”

Meaning: Dangerous ground or a topic that it is dangerous to discuss

“No man’s land” was widely used by soldiers to describe the area between opposing armies in their trenches in World War I. It was then morphed to describe any area that it was dangerous to stray into or even topics of conversation that could anger another speaker. However, this is one case where civilians borrowed a military phrase that the military had stolen from civilians. “No man’s land” was popularized in the trenches of the Great War, but it dates back to the 14th century England when it was used on maps to denote a burial ground.

11. “Nuclear option”

Meaning: A choice to destroy everything rather than give in on a debate or contest

Used most publicly while discussing fillibusters in the Senate, the nuclear option has its roots in — what else — nuclear warfare. In the Cold War, military leaders would give the commander-in-chief options for the deployment and use of nuclear weapons from nuclear artillery to thermonuclear bombs. In the era of brinksmanship, use of nuclear weapons by the Soviets or the U.S. would likely have ended in widespread destruction across both nations.

12. “On the double”

Meaning: Quickly, as fast as possible

Anyone who has run in a military formation will recognize the background of “on the double.” “Quick time” is the standard marching pace for troops, and “double time” is twice that pace, meaning the service member is running. Doing something “on the double” is moving at twice the normal speed while completing the task.

13. “On the frontlines”

Meaning: In the thick of a fight, argument, or movement

Like nuclear option, this one is pretty apparent. The front line of a military force is made up of the military units closest to a potential or current fight. Troops on the frontline spend most days defending against or attacking enemy forces. People who are “on the frontlines” of other struggles like political movements or court trials are fighting against the other side every day. This is similar in usage and origin to “in the trenches” above.

14. “Roger that”

Meaning: Yes

This one is pretty common knowledge, though not all civilians may know why the military says, “Roger that,” rather than “yes.” Under the old NATO phonetic alphabet, the letter R was pronounced, “Roger” on the radio. Radio operators would say, “Roger,” to mean that a message had been properly received. The meaning evolved until “roger” meant “yes.” Today, the NATO phonetic alphabet says, “Romeo,” in place of R, but “roger” is still used to mean a message was received.

15. “Screw the pooch”

Meaning: To bungle something badly

“Screw the pooch” was originally an even racier phrase, f*ck the dog. It meant to loaf around or procrastinate. However, by 1962 it was also being used to mean that a person had bungled something. Now, it is more commonly used with the latter definition.

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