House counterpart (6)
I believe the answer is:
senate
'house counterpart' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for senate that I've seen before include "The upper house in parliament or oireachtas" , "Second house of Government" , "Political body" , "Legislative assembly" , "Second house of the Oireachtas" .)