Place appointed for a picket (4)
I believe the answer is:
post
This clue could be a double definition.
'place appointed for' is the first definition.
'post' can be an answer for 'place' (synonyms). I'm not sure about the 'appointed for' bit.
'a picket' is the second definition.
(I've seen this before)
Can you help me to learn more?
(Other definitions for post that I've seen before include "Prefix meaning after" , "Prevent (cheque) being cashed immediately" , "Stake, job or mail" , "Mail; office" , "Job; upright timber" .)