Back rents suitably adjusted (5)

I believe the answer is:

stern

I'm a little stuck... Click here to teach me more about this clue!

'back' is the definition.
(stern is a kind of back)

'rents suitably adjusted' is the wordplay.
'rents' can be anagrammed to 'STERN'.
Though, I'm not sure how this is indicated.

Can you help me to learn more?

(Other definitions for stern that I've seen before include "Severe -- back of boat" , "Strict - forbidding" , "enforcing submission" , "Austere rear part of a ship?" , "Rear; severe, serious" .)

I've seen this clue in The Globe and Mail.

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