Support clown putting out rubbish (4)
I believe the answer is:
pier
'support' is the definition.
(pier is a kind of support)
'clown putting out rubbish' is the wordplay.
'clown' becomes 'pierrot' (I've seen this before).
'putting out' is a deletion indicator.
'rubbish' becomes 'rot' (I've seen this before).
'pierrot' with 'rot' taken out is 'PIER'.
(Other definitions for pier that I've seen before include "'Dock, wharf (4)'" , "Building projecting into the sea" , "Wharf jutting out into water" , "sight at the seaside" , "Ripe as a jetty (4)" .)