Action: A live bet or bets. ("They got a lot of action on that game." "I have action on this game.")

Arbitrage: Betting the same event at separate sports books in order to lock in a profit by taking advantage of different betting lines.

Bad beat: A very tough, often emotional, betting loss that is characterized by rotten luck.

Bankroll: Total capital available for betting sports.

Beard: A person who is betting someone else's money for that other person; a messenger.

Board: A presentation of all the games and events available for betting in a sports book. (If wagers are being taken on a game, the game is "on the board," otherwise it is "off the board.")

Bookmaker (or bookie): A person who accepts bets.

Buck: See "dollar."

Buyback: The money that comes in on the underdog after a favorite is bet heavily enough to move the line.

Chalk: A favorite, usually a heavy favorite.

Chalk eaters: Bettors who like to bet big favorites (often a derogatory term).

Circled game: A game in which the sports book has reduced its betting limits, usually because of weather or the uncertain status of injured players.

Cover: Winning against the point spread. (A 10-point underdog that loses 20-14 has covered, or "covered the spread.")

Dime: $1,000. (A "five-dime" bet is a $5,000 bet.)

Dime line: A betting line with a 10-cent straddle, often used in baseball. (With a dime line, if the favorite is minus 120, the underdog is plus 110.)

Dog: See "underdog."

Dollar: $100. (If a sports book has a $500 maximum on a particular type of bet, you could say it's a "five-dollar limit.")

Exposure: The degree of risk that a sports book will lose money on a given game, result or proposition. (If a book is "highly exposed" on the Cubs in World Series futures betting, it will lose a lot of money to bettors if the Cubs win the World Series.)

Fade: To take the opposite side of another bettor's wager or to accept that bet yourself.

Favorite: A team (or player) that, according to the odds, is the stronger or strongest in a given match-up or is regarded as such by the betting public or is expected to win.

First-half betting: Wagers that involve the outcome of the first half of a game only.

Freeroll: A bet you can win or push but not lose.

Futures: A type of wager involving the outcome of a season or how a particular team or player will perform over the course of a season.

Halftime betting: Wagers, based on betting lines posted at halftime, which involve the outcome of the second half of a game only.

Handicap: To study and research sports in order to make predictions on the results of upcoming games and events.

Handle: The amount of money in wagers accepted. ("The handle was down this year on the Super Bowl.")

Hedge: To make a bet that takes the opposite side of your original position, usually to reduce risk or lock in some profit.

Hook: A half-point in the betting spread. ("I lost by the hook.")

Hotel guest: See "tourist."

House: The casino, sports book or bookmaker.

Juice: See "vigorish."

Layoff: A type of wager made by one bookmaker with another, often larger, bookmaker in order to balance action or reduce risk.

Limit: The maximum wager accepted by a sports book.

Line: The point spread or odds on a game or event.

Lock: A bet that cannot lose; a term that is often misused and abused by disreputable touts.

Long shot: Big underdog.

Match-up proposition: A betting option that pits two players against one another in a contest or event, often used in golf and auto racing wagering.

Middle: A situation in which you bet both sides in a game and win both bets, due to favorable line moves. (Example: Bet a football favorite at minus 2 ½, then bet the underdog at plus 3 ½ at another book or later in the week. If the favorite wins by exactly 3 points, both bets win.)

Money line: The odds on a team winning a game outright, regardless of the point spread.

Money management: Any strategy used by a bettor for making the most of his bankroll.

Nickel: $500.

Offshore: Designation for the organized sports betting industry outside of the United States.

Out: A place to get bets down, whether it's a Nevada sports book, offshore book or illegal bookmaker. ("It's good to have a lot of outs.")

Over/under: See "totals."

Overlay: A situation in which the odds are favorable to the sharp bettor.

Parlay: A bet in which two or more events must happen in order to win; if any one of them does not happen, the wager loses.

Pay by mail: How sports books usually pay off winning tickets to tourists who make a bet while visiting Nevada, then return to their home state before they have a chance to cash them.

Pick 'em: An even match-up, a game with no clear favorite.

Player: A sports bettor.

Pleaser: A specialized form of a parlay that improves the point spread (for the book) but pays off at improved odds.

Point spread: The number of points added to or subtracted from a team's actual score for betting purposes.

Power rating: A numerical representation of a team's strength for betting purposes.

Price: See "line."

Proposition (or prop): An unusual or offbeat betting opportunity.

Public: Average, unsophisticated or casual bettors as a whole; or, used to describe money bet by the public ("a lot of public money came in on the Cowboys"); see "square."

Puck line: In hockey, a betting structure that dictates the favorite must win by a set number of goals, and/or adds a set number of goals to the underdog's actual score.

Pup: See "underdog."

Push: A bet in which the money wagered is refunded; a tie.

Rotation: The official list of all the games on the betting board, presented in a specific order.

Round robin: A specialized form of a parlay that uses every combination of a set of teams in a wager. For example, there would be six two-team parlays within a four-team round robin.

Rundown: A reading of all the games and betting lines on a particular day.

Runner: See "beard."

Scalp: A form of a middle in which you bet both sides in a game, taking advantage of line movements to secure a profit.

Sharp: Savvy, highly informed; or, used to describe the money bet by sharp players ("a lot of sharp money came in on the Eagles").

Side: A variation of a middle in which you win one bet and push the other; also, a particular team in a match-up. ("Which side do you like?")

Sports book: The part of the casino that accepts bets on athletic contests.

Square: An unsophisticated or casual bettor, the opposite of a wise guy; see "public."

Steam: One-sided action.

Straight: A single bet, usually laying 110 to win 100.

Takeback: On a money line, the price of the underdog. (In baseball, if the favorite is minus 120, the "takeback" on the underdog is often plus 110.)

Teaser: A specialized form of a parlay that improves the point spread (for the bettor) but pays off at reduced odds.

Totals: A type of wager that involves whether a score or result will go over or under a posted number.

Tourist: A typical visitor to Las Vegas, almost always used as another way to say "square."

Tout: A person who sells his predictions to bettors (often derogatory).

20-cent line: A betting line with a 20-cent straddle, standard in football and basketball. (With a 20-cent line, if the favorite is minus 120, the underdog is even money.)

Underdog: A team (or player) that, according to the odds, is the weaker or among the weakest in a given match-up, or is regarded as such by the betting public, or is expected to lose.

Vigorish (or vig): The commission charged by the bookmaker.

Wise guy: A sharp, successful, established professional sports bettor. (In terms of Las Vegas sports betting, this has nothing to do with Tony Soprano, Henry Hill & Co.)