MI5

[em-ahy-fahyv]

noun

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

MI5

abbreviation

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

Word History and Origins

Origin of MI5¹

M(ilitary) I(ntelligence, Section) 5

Example Sentences

But given the sensitivities of this judgement call, many others have been consulted – including MI5 and MI6.

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Earlier this week MI5 issued an alert to MPs and peers, warning they faced a significant risk of spying from the Chinese state.

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Former Panorama reporter Bashir secured the interview with Diana in 1995 after showing her brother faked bank statements that suggested people close to the princess were being paid by the security service MI5.

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Now it is the warning that all MPs and members of the House of Lords have received from the security service MI5 that they might be Beijing's next target.

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The question now is whether a moment like this, following MI5's intervention, persuades others to share their outlook.

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