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 a joint letter to the home secretary and foreign secretary about the embassy plans, MI5 director general Sir Ken McCallum and GCHQ's director Anne Keast-Butler said it was "not realistic to expect to be able wholly to eliminate each and every potential risk".

From BBC

Last week, families bereaved by the arena attack in 2017 wrote to him saying MI5 had failed them and argued that the proposed law must apply fully to security services.

From BBC

Last week, families of Manchester Arena attack victims wrote to the prime minister urging him to ensure the so-called Hillsborough Law applied to individual employees of MI5, MI6 and GCHQ.

From BBC

However, as things stand, the ancillary "duty of candour" will not fully apply to individual MI5 officers, unlike people who work for organisations such as the police.

From BBC

In their letter to Sir Keir Starmer last week, the families of five people killed in the Manchester bombing asked: "How many times must MI5 show that it cannot be trusted before something is done?"

From BBC