River where coat hauled up (3)
I believe the answer is:
cam
'river' is the definition.
(river in Cambridge, England)
'coat hauled up' is the wordplay.
'coat' becomes 'mac' (mac is a kind of coat).
'hauled up' says the letters should be written backwards.
'mac' backwards is 'CAM'.
'where' acts as a link.
(Other definitions for cam that I've seen before include "Rotating part in machine; river" , "East Anglian river" , "It controls the motion of engine cylinder valves" , "River; shaft projection" , "Shaft on a rotating part in machinery" .)