What does −110 mean in betting?

American odds. A minus number is what you must risk to win 100. A plus number is what you win by risking 100.

−110 means risk 110 to win 100, which is the market quietly saying "about a 52% chance." +200 means risk 100 to win 200, a 33% chance wearing a costume. Every moneyline is just a percent that's been made harder to read.

That's the whole reason Foresee skips the format. The percent is the only thing the number was ever trying to say, so we print the percent. If you're translating from a sportsbook: minus lines are favorites, plus lines are underdogs, and the bigger the number, the further from a coin flip.