Horse cut (4)
I believe the answer is:
hack
I believe this clue is a double definition.
'horse' is the first definition.
(hack is a kind of horse)
'cut' is the second definition.
(hacking is a kind of cutting)
(Other definitions for hack that I've seen before include "Drudge, inferior writer" , "Writer of uninspiring stuff" , "Cut crudely - journalist" , "persistent cough" , "Tired old horse" .)