Tool reinvented as a winch (8)
I believe the answer is:
chainsaw
'tool' is the definition.
(I've seen this before)
'reinvented as a winch' is the wordplay.
'reinvented' indicates an anagram.
'as'+'a'+'winch'='asawinch'
'asawinch' anagrammed gives 'CHAINSAW'.
(Other definitions for chainsaw that I've seen before include "Power tool" , "powered device" , "Timber cutter" , "woodcutter?" , "Tree-lopper's tool" .)