Renowned diarist (5)
I believe the answer is:
pepys
'renowned diarist' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for pepys that I've seen before include "Samuel ---, C seventeen Admiralty secretary" , "Samuel, diarist, d. 1703" , "Renowned diarist" , "Famous English diarist" , "English civil servant and diarist, d. 1703" .)