Tears off to look (5)
I believe the answer is:
stare
'to look' is the definition.
(I know this)
'tears off' is the wordplay.
'off' indicates an anagram.
'tears' with letters rearranged gives 'STARE'.
(Other definitions for stare that I've seen before include "Rates (anag.)" , "Look with fixed gaze" , "Gawp" , "Long fixed look" , "Look hard" .)