Old soldier welcomed by bookshop literati (7)
I believe the answer is:
hoplite
'old soldier' is the definition.
(I've seen this before)
'welcomed by bookshop literati' is the wordplay.
'welcomed by' indicates the answer is hidden within the clue.
'HOPLITE' is hidden in the letters of 'bookshop literati'.
(Other definitions for hoplite that I've seen before include "Foot-soldier" , "Infantryman" , "Old soldier" .)