Game people lose these going round the bend (7)
I believe the answer is:
marbles
This clue is a double definition.
'game' is the first definition.
(marbles is a kind of game)
'people lose these going round the bend' is the second definition.
(ref to the phrase 'losing one's marbles')
(Other definitions for marbles that I've seen before include "Sculptures" , "Children's game played with little balls" , "alleys, perhaps" , "Small spheres of glass - statuary" , "Glass balls to play with" .)