Weight loss affecting firmness of body ultimately (3)
I believe the answer is:
ton
'weight' is the definition.
(unit of weight)
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for ton that I've seen before include "People of fashion" , "Weight - fashion (French)" , "1000 kilos" , "Imperial unit of weight" , "20 cwt" .)