Look fixedly (5)
I believe the answer is:
stare
'look fixedly' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for stare that I've seen before include "'Look fixedly, without blinking (5)'" , "Rates (anag.)" , "Long fixed look" , "Gaze fixedly" , "Look with fixed gaze" .)