Letters sent or received (14)
![Ross](/clue/static/ross-mug.min.png)
I believe the answer is:
correspondence
'letters sent or received' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for correspondence that I've seen before include "close similarity" , "Letters sent or received" , "writing?" , "written communication" , "Close equivalence" .)