Stiff game? (5)
I believe the answer is:
poker
This clue could be a double definition.
'stiff' is the first definition.
Although both the answer and definition are singular nouns, I cannot see how they can define each other.
'game?' is the second definition.
(poker is a kind of game)
Can you help me to learn more?
(Other definitions for poker that I've seen before include "Epitome of stiffness" , "Popular gambling game with much bluffing" , "A game for the fireplace implement" , "Rod; betting game" , "Jabber" .)