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 in another clue).
'across' means one lot of letters goes inside another.
'the far side of' suggests the final letters.
The final letter of 'market' is 't'.
'peer' placed around '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" .)