(colloquial) when a
situation has reached a
stage at which
action or a
decision of great
importance must be taken. The expression comes from betting games where a player puts
chips or
money on the table to show how much he is willing to
risk. When all the
chips are down, the players have placed their bets, but it is still unknown who will
win and who will
lose.
—Grad V Approved 1992 Glossary Upgrade