Writer about to leave house (5)
I believe the answer is:
bingo
'house' is the definition.
(I've seen this before)
'writer about to leave' is the wordplay.
'writer' becomes 'nib' (something which writes).
'about' says the letters should be written in reverse.
'to' says to put letters next to each other.
'leave' becomes 'go' (**).
'nib' in reverse letter order is 'bin'.
'bin'+'go'='BINGO'
(Other definitions for bingo that I've seen before include "House!" , "Game of chance" , "Housey-housey" , "Number game" , "Popular gambling game in which numbers are called at random" .)