Lacking humour, husband no longer in the game (7)
I believe the answer is:
without
'lacking' is the definition.
(I've seen this in another clue)
'humour husband no longer in the game' is the wordplay.
'humour' becomes 'wit' (synonyms).
'husband' becomes 'h'.
'no longer in the game' becomes 'out' (knocked out of the game).
'wit'+'h'+'out'='WITHOUT'
(Other definitions for without that I've seen before include "Lacking; outside" , "Lacking; not inside" , "Free from: in the absence of" , "Not accompanied by" .)