Pork pie supported by, say, upstanding lord (5)
I believe the answer is:
liege
'lord' is the definition.
(feudal term for a superior)
'pork pie supported by say upstanding' is the wordplay.
'pork pie' becomes 'lie' ('pork pie' is Cockney rhyming slang for a lie).
'supported by' means one lot of letters go next to another (in a down clue, some letters hold up others).
'say' becomes 'eg' (both can mean for example).
'upstanding' says the letters should be written backwards.
'eg' reversed gives 'ge'.
'lie'+'ge'='LIEGE'
(Other definitions for liege that I've seen before include "European city" , "On about one East Belgium city" , "European province" , "Feudal (lord); vassal" , "Belgian, French-speaking city" .)