Tear off (6)
I believe the answer is:
detach
'tear off' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for detach that I've seen before include "Separate one part from another" , "Disengage (something) and remove it" , "Split off" , "Remove from something else, say a coupon" , "Separate from, remove part" .)