Look uncommon? (4)
I believe the answer is:
peer
'look' is the definition.
(to peer at something is to look at it)
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for peer that I've seen before include "Look closely at titled man?" , "Equal; nobleman" , "Gaze" , "Look closely at lord" , "Look hard at the nobleman" .)