Want half of mine to go to the boy (4)
I believe the answer is:
need
'want' is the definition.
(I know that want can be written as need)
'half of mine to go to the boy' is the wordplay.
'half of' indicates taking half.
'to go to' is a charade indicator (letters next to each other).
'the boy' becomes 'ed' (short for Edward).
'mine' with half the letters taken is 'ne'.
'ne'+'ed'='NEED'
(Other definitions for need that I've seen before include "state requiring relief" , "A condition" , "Necessity" , "''A friend in .... is a friend indeed''" , "What's lacking" .)