A situation in which each of two players have approximately equal chances of winning the pot.
ADDITIONAL INFORMATION: While a flip of an actual coin has a 50-50 chance of each of the two possible outcomes, the term may be used less strictly in poker. Example: During heads-up play in Texas Hold'em, a pocket pair has a slight percentage advantage against two overcards. The extent of the advantage varies depending on whether the overcards are suited and whether the cards used in the pocket pair are in the range that they might otherwise have helped the overcards complete a straight. Despite these variations, this situation is considered a coin flip.
EXAMPLE: "I busted out after going all-in on a coin flip."