Rabbit Hunt: When a player wins a pot without a showdown, some players want to know if they would have won had they stayed in the hand longer. They go ahead and ask the dealer to show what cards would have hit the board if they would’ve stayed in the hand till showdown. This behaviour is considered inappropriate.

Rack: Tray that usually holds 100 poker chips.

Rags: Useless cards or cards that don’t improve your hand.

Rags to riches: To be in the big blind with a hand you wouldn’t normally call (i.e. 2-3 offsuit), but since you are in the big blind you check. With your rags(2,3 of different suits), the flop comes A-4-5. You just went from rags to riches.

Rail: The rim of a poker table or a barrier outside a poker area.

Railbird(s): Player(s) who hang(s) around a poker room who watch(es) the games and/or is/are looking to get into action.

Rainbow: A flop which is of three different suits or a board in general which can’t compile a flush (i.e. two clubs, two hearts, one spade – even with two suited hole cards you can’t compile a flush).
Raise: To make an even larger bet than the previous bet.
Rake: Chips taken from the pot by the house for compensation for hosting the game.

Ratholing: Ratholing means to leave a game and then come back into the game with a smaller stack then with which you left (i.e. you’re winning and are uncomfortable with that much money on the table you cash out (let’s say 100$) and come back right away to buy in with 20$). This is considered bad etiquette and prohibited in most poker rooms.

Re-draw: This term is used to describe when a player who has a made hand is drawn out by another player. Then, on the river, the original player with the made hand draws another card to beat the person who drew out on him on the turn.

Ring game: see cash game

River: also known as fifth street. Final card of the board in Omaha and Hold’em.

Riverboat: Full House which was completed (rivered) by the river card.

Rock: This is a nickname for a type of player who will fold a lot. These players generally break even. They fold most of their losers, but will not aggressively bet their winners and will thus not make much money. They are also easily bullied out of pots.

Roger: Starting hand of 10-4.

ROI: ROI is short for “return on investment.” This is a poker term that is used to measure the profitability of one’s play in poker tournaments. ROI is calculated as (100 * total profit/total buy-in).

Rope-a-dope: To slowplay an opponent when you’re holding the nuts, this usually involves a lot of acting and feigning weakness in order to get your opponent(s) to bet/raise big on a bluff or weaker hand.

Route 66: Starting hand of pocket sixes.

Royal Flush: The best hand in poker (excluding 5 of a kind which can only be achieved with wildcards). The royal flush is the best possible straight flush – 10 to Ace in one suit.

Runner: The last card that was dealt helped a player. Usually it’s used as runner, runner when someone hits two cards of the same suit to make his flush, two consecutive cards of the same rank to compile a full house or four of a kind, etc.

Rush: Winning streak.