Said to push in opposite directions (6)
I believe the answer is:
spoken
'said' is the definition.
(I've seen this in another clue)
'push in opposite directions' is the wordplay.
'push' becomes 'poke' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'in' means one lot of letters goes inside another.
'opposite directions' becomes 'SN' (opposite compass points).
'poke' put inside 'sn' is 'SPOKEN'.
'to' is the link.
Can you help me to learn more?
(Other definitions for spoken that I've seen before include "Voiced" , "Oral" , "Uttered through the medium of speech" , "released from trap" , "Said" .)