Collar that has number turned up (3)
I believe the answer is:
net
'collar' is the definition.
(both can mean to apprehend)
'number turned up' is the wordplay.
'number' becomes 'ten' (ten is a kind of number).
'turned up' says the letters should be written backwards.
'ten' in reverse letter order is 'NET'.
'that has' acts as a link.
(Other definitions for net that I've seen before include "Mesh; after tax" , "Fish-catching mesh" , "Mesh or web" , "Amount remaining after deductions" , "Make" .)