Firm receiving instruction's reported (4)

I believe the answer is:

taut

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'firm' is the definition.
(I've seen this in another clue)

I don't understand the rest of the clue.

(Other definitions for taut that I've seen before include "On the slope" , "Stretched tight or disciplined" , "Fully stretched" , "Tense, stretched tight" , "Pulled or drawn tight" .)

I've seen this clue in The Daily Mail.

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