Closing Line

The commission or fee built into the odds by the bookmaker. Also known as vigorish (vig), it represents the bookmaker's profit margin. For example, if both sides of a coin flip are priced at 1.91 instead of 2.00, the difference is the juice. Lower juice means better value for bettors.

A sudden and significant shift in a betting line caused by a large volume of sharp money on one side. Steam moves happen quickly across multiple bookmakers as they adjust their odds. These moves often signal that professional bettors have identified a strong edge.

A common British and Australian term for a person who places bets, particularly on horse racing and sports. In the US, the equivalent term is typically 'bettor' or 'gambler'. The term is used casually and does not imply any particular skill level.

The advantage a bettor has over the bookmaker on a particular bet. An edge exists when the bettor's estimated probability of an outcome is higher than the implied probability of the odds offered. Finding and exploiting edges is the foundation of profitable betting.

The maximum amount a bookmaker or a lay bettor stands to lose on a single bet. For bookmakers, liability is managed across thousands of bets. On a betting exchange, when you lay a bet, your liability is the amount you must pay the backer if they win. Understanding liability is essential for exchange betting.

The amount of money a bettor risks on a single wager. Proper stake sizing is a critical component of bankroll management. Most professional bettors recommend risking between 1% and 5% of your total bankroll on any single bet to minimize the risk of ruin.