Hand is in foot? (4)
I believe the answer is:
fist
'hand' is the definition.
(fist is a kind of hand)
'is in foot?' is the wordplay.
'in' is an insertion indicator.
'foot?' becomes 'ft' ('ft' can be a synonym of 'foot').
'is' placed within 'ft' is 'FIST'.
(Other definitions for fist that I've seen before include "or be decked in a ring" , "duke" , "Tightly-closed hand" , "Hit with a clenched one" , "Balled hand" .)