Game trap suspicious -- mysteriously empty (3,5)
I believe the answer is:
gin rummy
'game' is the definition.
(card game)
'trap suspicious mysteriously empty' is the wordplay.
'trap' becomes 'gin' (gin trap is a kind of animal trap).
'suspicious' becomes 'rum' (rum can mean strange or dubious).
'empty' means to remove the middle letters.
'mysteriously' with its middle removed is 'my'.
'gin'+'rum'+'my'='GIN RUMMY'
(Other definitions for gin rummy that I've seen before include "cards" , "Card game" .)