Post the ends off (4)
I believe the answer is:
send
'post' is the definition.
('send' can be a synonym of 'post')
'the ends off' is the wordplay.
'off' indicates an anagram.
'ends' is an anagram of 'SEND'.
(Other definitions for send that I've seen before include "Transmit (message)" , "Sentence to a prison term" , "Mail" , "Transport" , "and 2: Advise" .)