In the popular multiplayer shooter Team Fortress 2(tm) made by Valve(tm), spies are a nuisance. They run around, backstabs players and disguises as players. But above all else, they are SAPPIN' MAH SENTRY!

An engineer builds stuff. A spy saps the stuff the engineer builds, and utterly destroys it in a matter of seconds. Naturally, they are really annoying. The engineer thinks so as well. That's why he yells out "Spy's sappin' mah sentry" in pure fear and helplessness.

Also the inspiration to "spy's a spy!", created using digital soundboards.

The phrase is mostly used to describe a sense of fear, despair or pure hate when someone completely ruins whatever you're trying to accomplish.
For the love of God, SPY'S SAPPIN' MAH SENTRY!
by Realmen.Inc May 8, 2008
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In the Navy and Marine Corp there are 11 General Orders of a Sentry, however there are an unofficial twelfth and thirteenth referred to by many.
RDC to Recruit: "What is the "13th General Order of a Sentry?"

Recruit to RDC: "To walk my beat, beat my meat, and fuck/shoot anything within 50 feet."
by Little Dickie January 4, 2009
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There are 11 General Orders of a Sentry, however there is a twelth refered to by many Navy."To walk my post from flank to flank and take no shit from any rank. If he is a chief I will let him pass, if he is an officer he can kiss my a**."
The 12th General Order of a Sentry is fairly close to the 11th in meaning
by EmilyElizabeth July 20, 2008
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An addition to the 11 General Orders of a Sentry (or watchstander) in the United States Military.

12.)"Don't Get Caught"

1) To take charge of this post and all government property in view.
2) To walk my post in a military manner, keeping always on the alert and observing everything which takes place within sight or hearing.
3) To report all violations of orders I am instructed to enforce.
4) To repeat all calls from posts more distant from the guard house than my own.
5) To quit my post only when properly relieved.
6) To receive, obey, and pass on to the sentry who relieves me, all orders from the Commanding Officer, the Officer of the Day, and all officers and non-commissioned officers of the guard only.
7) To talk to no one except in the line of duty.
8) To give the alarm in case of fire or disorder.
9) To call the Corporal of the Guard in any case not covered by instructions.
10) To salute all officers and all colors and standards not cased.
11) To be especially watchful at night and during the time for challenging, to challenge all persons on or near my post, and to allow no one to pass without proper authority.
"Dude's getting busted for drinkin underage. That sucks!"
"Hey - its his fault he broke the 12th General Order of a Sentry"
by navy sailor April 18, 2006
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The Navy, like the Marine Corps, has 11 published General Orders of a Sentry.

However, since the first orr dipped into the water, Sailors have been smart-asses, if you give us 11 refined General Orders, we will give you back a vulgar 12th.

The 12th General Order of a Sentry is:
To walk my beat and beat my meat and fuck everything with in 15ft,
And Sir/Ma'am you are too fucking close!

This Definition is circa 1981, Naval Recruit Training Center, San Diego CA.
How the phase The 12th General Order of a Sentry - Navy , would be used
Officer: Recruit what is your 12th General Order !
Recruit: Sir/Ma'am, My 12th General Order is .... !
by FuzzyNavy April 9, 2018
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A biased bum that gets slammed in every debate because he can't accept facts and bitches out half way in because he can't debate also he gets his back blown out every night after sucking sentries dick before he goes to bed
by Dmoney 69 August 6, 2021
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