Punch higher and lower (8)
I believe the answer is:
uppercut
'punch' is the definition.
(I've seen this before)
'higher and lower' is the wordplay.
'higher' becomes 'upper' (higher up).
'and' is a charade indicator (letters next to each other).
'lower' becomes 'cut' (I've seen this before).
'upper'+'cut'='UPPERCUT'
(Other definitions for uppercut that I've seen before include "Punch to opponent's chin from below" , "Swinging blow from below aimed at an opponent's chin" , "Swinging blow in boxing" , "Blow from fist to chin" , "Type of punch" .)