Helicopter carrying foolish old peasant (10)
I believe the answer is:
clodhopper
'peasant' is the definition.
(thesaurus)
'helicopter carrying foolish old' is the wordplay.
'helicopter' becomes 'chopper' ('chopper' can be a synonym of 'helicopter').
'carrying' is an insertion indicator.
'foolish' indicates anagramming the letters.
'old' anagrammed gives 'lod'.
'chopper' enclosing 'lod' is 'CLODHOPPER'.
(Other definitions for clodhopper that I've seen before include "Clumsy fellow" , "Clumsy type" , "bumpkin" , "Hold copper (anag)" , "Clumsy person - heavy shoe" .)