A stake is a wooden stick, sharpened on one end and used to mark property lines (or slay a vampire). In the Middle Ages, people would gamble by placing their bets on wooden posts, or stakes. Eventually the bets themselves became known as stakes.

The first number in the fraction indicates the potential profit, while the second number represents the stake. For instance, if you betR$100 on a team with odds of 3/1, you would winR$300 ($100 x 3) plus your original stake ofR$100, resulting in a total payout ofR$400.