Old farm worker with bald head stands out in jail (6,4)
I believe the answer is:
behind bars
'in jail' is the definition.
(I've seen this before)
'old farm worker with bald head stands out' is the wordplay.
'old farm worker' becomes 'hind'.
'with' means one lot of letters go next to another.
'head' says to take the initial letters.
'stands' becomes 'bears' ('bear' can be a synonym of 'stand'**).
'out' is an insertion indicator.
The initial letter of 'bald' is 'b'.
'hind'+'b'='hindb'
'hindb' going into 'bears' is 'BEHIND BARS'.
(Other definitions for behind bars that I've seen before include "In jail" , "being detained?" , "Where drinks are kept" , "under lock and key" , "Incarcerated" .)