To conceal in the hand (4)
I believe the answer is:
palm
'to conceal in the hand' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for palm that I've seen before include "that's inspected by a fortune-teller" , "Evergreen tree and part of the hand" , "Tropical tree; conceal" , "Underside of hand" , "Sign of victory" .)