MI5

American  

[em-ahy-fahyv] / ˈɛmˌaɪˈfaɪv /

noun

1. the government's security and counterespionage service that works in liaison with Scotland Yard's Special Branch.

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MI5 British  

abbreviation

1. Military Intelligence, section five; a former official and present-day popular name for the counterintelligence agency of the British Government

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Etymology

Origin of MI5

M(ilitary) I(ntelligence, Section) 5

Compare meaning

How does mi5 compare to similar and commonly confused words? Explore the most common comparisons:

• MI5 vs. MI6

Example Sentences

In November, Britain's domestic intelligence agency MI5 warned that China was using spies disguised as head-hunters to recruit parliamentarians, through LinkedIn among others.

From Barron's

It cites the case of Gill, and of the MI5 alert against Christine Lee, as examples of where the public have been alerted to techniques that can be used.

From BBC

But some campaigners pointed to the behaviour of intelligence agencies after the Manchester Arena bombing, when MI5 was accused of misleading the inquiry into the incident.

From BBC

He even tried to bring a private prosecution against MI5 in August 2024 for an alleged assault.

From BBC

An IT specialist working for MI5 on a contract who disclosed intelligence information to a "foreign power" has been found "not guilty by reason of insanity" by an Old Bailey jury.

From BBC