Clue penned by wordsmith in Times (4)
I believe the answer is:
hint
'clue' is the definition.
('hint' can be a synonym of 'clue')
'penned by wordsmith in times' is the wordplay.
'penned by' indicates the answer is hidden within the clue.
'HINT' can be found hidden inside 'wordsmith in times'.
(Other definitions for hint that I've seen before include "Small trace; clue" , "CRT screen coating" , "'Slight indication, indirect suggestion (4)'" , "Tip, clue" , "Clue - soupcon" .)