Second sight, for short (3)
I believe the answer is:
esp
'second sight for short' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for esp that I've seen before include "Second sight (abbr)" , "Apparent power to perceive things that others can't, initially" , "Extrasensory perception (abbrev.)" , "Initially, clairvoyance or telepathy" , "Apparent power to perceive things that others can't, in short" .)