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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

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
slip of the tongue perhaps,
Those idiots who drive around in a ridiculously raised pick up truck, making a top heavy vehicle even more top heavy and unstable
A:*gah*
B: "Whats the matter"
A: This dam prickup is blinding me.
B: Stupid thing's, as if there lights weren't blinding enough as it is.
prickup by lunasea September 28, 2009
Word of the Day on June 23, 2026

Serial Monogamist 

Someone who jumps from one relationship immediately into another one.

Serial monogamists can not stand to be alone and often suffer from vast commitment and insecurity issues.

Because they jump into relationships immediately after the previous one has ended, serial monogamists typically don't take the time to reflect on their behavior or why their previous relationships failed; thus, they end up making the same relationship mistakes over and over again.
Person 1: Damn, Dustin already has a new girlfriend?! It's only been two weeks since he broke up with his fiance! I think he's a sociopath.

Person 2: No, he's a serial monogamist...
Word of the Day on June 22, 2026