Fastened up again (3)

I believe the answer is:

did

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'fastened' is the definition.
Although both the answer and definition are past participle verbs, I can't understand how one could define the other.

I don't understand the remainder of the clue.

Can you help me to learn more?

(Other definitions for did that I've seen before include "Achieved; cheated" , "Carried out an act" , "was satisfactory" , "Swindled" , "Performed an action" .)

I've seen this clue in the Evening Standard.

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