Perceive hare running (4)
I believe the answer is:
hear
'perceive' is the definition.
(hearing is a kind of perceiving)
'hare running' is the wordplay.
'running' indicates an anagram (the letters run around to different places).
'hare' with letters rearranged gives 'HEAR'.
(Other definitions for hear that I've seen before include "learn" , "attend" , "receive information" , "Pay attention" , "Listen to" .)