side bet
noun
a bet made, as with another player, in addition to one's principal bet: a side bet as to which of us would draw the highest card.
Origin of side bet
First recorded in 1890–95
Words nearby side bet
side,
side against,
side arm,
side arms,
side band,
side bet,
side boob,
side by side,
side card,
side chain,
side chair