Sellers gaze across the far side of market (5)
I believe the answer is:
peter
'sellers' is the definition.
(I've seen this in another clue)
'gaze across the far side of market' is the wordplay.
'gaze' becomes 'peer' (I've seen this before).
'across' is an insertion indicator.
'the far side of' says to take the final letters.
The last letter of 'market' is 't'.
'peer' enclosing 't' is 'PETER'.
(Other definitions for peter that I've seen before include "Safe - name for a man" , "-- Sellers, comic actor" , "and 16: Actor who played Hercule Poirot" , "Early Pope" , "- Sellers, twentieth century English comedian" .)