Some chicken leg remains from a classic order (9)
I believe the answer is:
parthenon
'remains from a classic order' is the definition.
(building in classical architectural order)
'some chicken leg' is the wordplay.
'some' becomes 'part' (only part of something).
'chicken' becomes 'hen' (hen is a kind of chicken).
'leg' becomes 'on' (cricket term, fielding positions).
'part'+'hen'+'on'='PARTHENON'
(Other definitions for parthenon that I've seen before include "ruined Greek temple" , "Tourist attraction of Athens" , "Ancient temple" , "Temple of Athene on Acropolis in Athens" , "Temple on the Athenian Acropolis" .)