Young cow kept in local farm (4)
I believe the answer is:
calf
'young cow' is the definition.
(a calf is a young cow)
'kept in local farm' is the wordplay.
'kept in' indicates a hidden word.
'CALF' is hidden within 'local farm'.
(Other definitions for calf that I've seen before include "Back of lower leg" , "A little lower" , "Baby cow" , "Young cow or bull" , "Young moo-er" .)