The boy from the ministry (3)

I believe the answer is:

mod

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'ministry' is the definition.
(Ministry of Defence)

I don't understand the remainder of the clue.

(Other definitions for mod that I've seen before include "Rocker's rival?" , "ministry" , "1960s teenager" , "Meeting of the Scottish" , "Gaelic literary festival" .)

I've seen this clue in the Evening Standard.

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