Tree from Nepal, mostly (4)
I believe the answer is:
palm
'tree' is the definition.
(palm is a kind of tree)
'from nepal mostly' is the wordplay.
'from' indicates a hidden word.
'PALM' is hidden in the letters of 'nepal mostly'.
(Other definitions for palm that I've seen before include "Sign of victory" , "Tree with no branches and large leaves" , "prize" , "Evergreen tree and part of the hand" , "Conceal in the hand" .)