Animal pen in West Yorkshire (3)
I believe the answer is:
sty
'animal pen' is the definition.
(enclosure for pigs)
'in west yorkshire' is the wordplay.
'in' says the answer is hidden in the clue.
'STY' is hidden in the letters of 'west yorkshire'.
(Other definitions for sty that I've seen before include "Pig home or eye sore" , "Swinish place" , "Sore on eyelid" , "See 15" , "Pig pen" .)