Depression hit British member of parliament (9)
I believe the answer is:
punchbowl
'depression' is the definition.
(I have seen 'deep depression' mean 'punchbowl' so perhaps 'depression' could also mean 'punchbowl')
'hit british member of parliament' is the wordplay.
'hit' becomes 'punch' (punching is a kind of hitting).
'british' becomes 'b' (abbreviation e.g. in 'BBC').
'member of parliament' becomes 'owl' ('parliament' is the collective noun for 'owl').
'punch'+'b'+'owl'='PUNCHBOWL'
(Other definitions for punchbowl that I've seen before include "Large receptacle for mixing drink" , "deep depression" , "Source of drink" , "where one mixes at a party" , "Drinking vessel" .)