CO河牌加注后弃牌（彩虹牌面）（CO River Raise-Fold Rainbow）

Term Explanation

CO River Raise-Fold Rainbow describes a specific decision scenario in No-Limit Texas Hold'em: a player in the cutoff (CO, the position to the right of the button) raises on the river, but then folds when facing a re-raise from an opponent. Additionally, the board is a "rainbow," meaning the flop, turn, and river are all of different suits, eliminating the possibility of a flush draw or a completed flush.

Strategic Significance

This term is commonly used to analyze a player's range and decision logic. A raise from the CO on the river may indicate a value bet with a made hand (such as top pair or two pair) or a bluff attempt. However, folding after facing a re-raise suggests the player believes their hand is not strong enough to beat the opponent's raising range, or they infer the opponent holds a stronger hand. The rainbow board reduces flush possibilities, so the opponent's raise is more likely to come from a strong made hand or the nuts. This "raise then fold" behavior may theoretically be a way to cut losses after a failed value raise, or a mixed strategy tailored to a specific opponent.

Typical Example

Assume a $1/$2 No-Limit Hold'em game. The CO player holds K♠Q♥. The flop is 8♣5♦2♥ (rainbow), the turn is 10♣, and the river is 3♦ (still rainbow). The CO bets $10, and the opponent raises to $30. The CO suspects the opponent has at least two pair or three of a kind, and since the board has no flush draw, they decide to fold. This sequence constitutes a CO River Raise-Fold Rainbow.

Notes

• This term is not an official poker term but a specific scenario description coined by the player community and is often used in strategy discussions.
• "Rainbow" here emphasizes that the board has no flush threat, making the opponent's raise more indicative of hand strength.