X, to Xenophon (3)
I believe the answer is:
chi
'x to xenophon' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for chi that I've seen before include "character in Thessaloniki" , "Greek character" , "Greek letter; force in Chinese philosophy" , "foreign character" , "seen in Greek writing" .)