Put in post — collection around noon (4)
I believe the answer is:
sent
'put in post' is the definition.
(sent via the post)
'collection around noon' is the wordplay.
'collection' becomes 'set' (set is a kind of collection).
'around' is an insertion indicator.
'noon' becomes 'n'.
'set' placed around 'n' is 'SENT'.
(Other definitions for sent that I've seen before include "Transmitted" , "Posted" , "Told to go - enthralled" , "charged with emotion?" , "Shipped" .)