Look, it could be injurious (4,3)
I believe the answer is:
evil eye
'look' is the definition.
(evil eye is a kind of look)
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for evil eye that I've seen before include "Supposedly harmful glance" , "Look that can be harmful?" , "Malign influence" , "Bad-luck look" , "Gaze superstitiously thought to bring harm" .)