Seeing return of predator, run! (4)
I believe the answer is:
flow
'run' is the definition.
(I've seen this before)
'seeing return of predator' is the wordplay.
'seeing return of' shows that the letters should be reversed in order.
'predator' becomes 'wolf'.
'wolf' written backwards gives 'FLOW'.
(Other definitions for flow that I've seen before include "Run or move like a liquid" , "(Forward) movement of liquid" , "Move along as a stream" , "Wolf (anag.)" , "Well forth" .)