Way grand house is mentioned (6)
I believe the answer is:
manner
'way' is the definition.
(I know that way can be written as manner)
'grand house is mentioned' is the wordplay.
'grand house' becomes 'manor' (I've seen this in another clue).
'is mentioned' shows a homophone (sound like).
'manor' sounds like 'MANNER'.
(Other definitions for manner that I've seen before include "Fashion, way" , "Way of doing something, or general attitude" , "Way in which something is done" , "Mode" , "Bearing; style of art" .)