Handle force in Panama perhaps (4)
I believe the answer is:
haft
'handle' is the definition.
(I know that haft is a type of handle)
'force in panama perhaps' is the wordplay.
'force' becomes 'f' (symbol used in Physics e.g. f=ma).
'in' indicates putting letters inside.
'panama perhaps' becomes 'hat' (Panama is a type of hat).
'f' inserted into 'hat' is 'HAFT'.
(Other definitions for haft that I've seen before include "Knife or axe handle" , "Handle (of e.g. axe)" .)