Pelt Henry with fish (4)
I believe the answer is:
hide
'pelt' is the definition.
('hide' can be a synonym of 'pelt')
'henry with fish' is the wordplay.
'henry' becomes 'h' ('H' can be a synonym of 'henry').
'with' says to put letters next to each other.
'fish' becomes 'ide' (I've seen this before**).
'h'+'ide'='HIDE'
(Other definitions for hide that I've seen before include "Fell" , "Secrete - animal skin" , "mask" , "A flower; an instrument" , "Animal retreat" .)