One involved in Yahtzee or Go (3)
I believe the answer is:
die
I believe this clue is a double definition.
'one involved in yahtzee' is the first definition.
(singular of dice. Yahtzee is a dice game)
'go' is the second definition.
(I know that go can be written as die)
'or' acts as a link.
(Other definitions for die that I've seen before include "Numbered cube" , "rolling over - to do this?" , "Cease to exist" , "Give out" , "One spotted" .)