Cutter, dreadfully chesty (6)
I believe the answer is:
scythe
'cutter' is the definition.
(I know that scythe is a type of edge tool)
'dreadfully chesty' is the wordplay.
'dreadfully' indicates anagramming the letters (a dreadful spelling).
'chesty' is an anagram of 'SCYTHE'.
(Other definitions for scythe that I've seen before include "Implement with curved blade" , "Old farming tool" , "Crop cutting blade" , "Old mowing implement for hand use" , "Reaping blade" .)