Heavy weight that's not raised (3)
I believe the answer is:
ton
'heavy weight' is the definition.
(a ton weighs a lot)
'not raised' is the wordplay.
'raised' shows that the letters should be reversed in order (going up in a down clue).
'not' written backwards gives 'TON'.
'that's' is the link.
(Other definitions for ton that I've seen before include "Two thousand, two hundred and forty lbs avoirdupois" , "Unit of weight equivalent to 20 cwts" , "Heavy weight or 100mph" , "20 cwt" , "See 25" .)