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(UK GOVERNMENT) British intelligence agency. Under the Home Secretary (w/in the British Cabinet), along with MI-6 and Government Communications Headquarters (GCHQ).

A few points: MI-5 can be written MI5. It differs from MI-6 (or MI6) in that MI-5 houses one group of specialized functions, and MI-6 houses another group. Both were founded in 1909 to supervise existing agencies of the Admiralty and the War Office. MI-5 tended to specialize in counterespionage on UK soil, but it also carried out espionage against trade union officials and Labour politicians in the UK.

Since the end of the Cold War it has focused on counterterrorism activities.
Contrary to some definitions elsewhere, MI-5 was not involved in Operation Ajax; that was carried out by the Secret Intelligence Service (SIS), also known as MI-6, as well as the US CIA.
MI-5 by Primus Intra Pares July 19, 2010
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The British domestic and foreign counterintelligence service responsible for national internal security.
Military Intelligence, section five; a former official and present-day popular name for the counterintelligence agency of the British Government. MI5 was formed in 1909 as the Secret Service Bureau.
MI5 by Dancing with Fire September 5, 2012
Related Words
5th section of military intelligence.


British data gathering security service. Mainly concerned with internal affairs, as opposed to more field active MI6 (Think James Bond) which follows foreign affairs.
MI5 concern themselves with internal affairs and counter-espionage
MI5 by Gumba Gumba April 13, 2004
British intelligence agency.
They secretly have death squads that operate in Britain which disappear (murder) homeless people and other members of the public they deem unfit to live!
mi5. by Weal donald twump August 2, 2017
It is said of the situation where a person has the bad luck to make contact with his testicles against an undefined surface or object, intentioned or not.
Given the nature of the word, it is more appropriate to design cases where the interaction is made with a moving object, for example, a ball.
Although it is extremely painful for the victim, it tends to be considerably funny to people who witness it.
Today in the baseball game the pitcher took a nutshot; the baseball hit him in the nuts.

Man, I just watched the funniest nutshot video ever.
Nutshot by Uberflaven March 1, 2009
Word of the Day on June 26, 2026

Nerd neck 

A "human" that spends so much time playing video games that their posture is level nerd neck. Everytime anyone goes tryhard they hunch down and their neck gets longer there fore a nerd neck is always hunched down cause they're always going try hard. In other words a nerd neck is a try hard, since their neck is 100% longer than the average human being due to playing too many video games and taking them serious, nerd necks are not even considered human anymore but something more sad. Nerd necks are often found on fortnite, their natural habitat usually being tilted towers.
What a fucking nerd neck!

He is building so fast, nerd neck!

Looser more like a nerd neck ha!
Nerd neck by D Sandwich Maker February 5, 2019
Word of the Day on June 25, 2026

love peace and chicken grease 

"another of sayin peace out or good bye"
Talk to ya later......Love, Peace, and Chicken Grease
Word of the Day on June 24, 2026