Some deliveries friend sent back come together (7)
I believe the answer is:
overlap
'come together' is the definition.
(to overlap is to join with something else)
'some deliveries friend sent back' is the wordplay.
'some deliveries' becomes 'over' (I've seen this before).
'friend' becomes 'pal' (pal is a kind of friend).
'sent back' says the letters should be written in reverse.
'pal' reversed gives 'lap'.
'over'+'lap'='OVERLAP'
(Other definitions for overlap that I've seen before include "Outflank" , "Extend over and cover a part of" , "Common area of interest" , "Extend beyond edge of a thing and partly cover it" , "Lie partly on top of" .)