Get oddly meek rogue to join up (5)

I believe the answer is:

merge

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'join up' is the definition.

I don't understand how the rest of the clue works.

(Other definitions for merge that I've seen before include "Mix" , "Amalgamate" , "Join, blend" , "Combine, blend" , "Combine, coalesce" .)

I've seen this clue in The Irish Times.

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