Half of what makes a casino intimidating isn't the games - it's the vocabulary. Dealers rattle off "yo," "soft 17," "press your bet," and you nod along hoping nobody asks a follow-up. Here are the terms that actually come up at the table, in plain English, grouped by where you'll hear them.
General casino terms
House edge - the casino's built-in mathematical advantage on a bet, as a percentage of what you wager. The lower, the better for you. (How we compute it.)
Buy-in - the cash you exchange for chips when you sit down.
Comp - a freebie (meal, room, free play) the casino gives you based on how much you play, tracked by your players card.
Players card - a free loyalty card that logs your play to earn comps. It doesn't change your odds.
Toke - a tip for the dealer, often made as a small bet on their behalf.
Marker - casino credit extended to a player; also the puck used in craps to mark the point.
Press - to increase a bet, usually by adding your winnings to it.
Color up - to swap your small chips for larger denominations before leaving a table.
Craps terms
Come-out roll - the first roll of a round, when 7 and 11 win the Pass Line and 2, 3, 12 lose. (How to play craps.)
Point - the number (4, 5, 6, 8, 9, or 10) set on the come-out that the shooter must repeat before a 7.
Seven-out - rolling a 7 after the point is set; the Pass Line loses and the dice pass to the next shooter.
Shooter - the player currently rolling the dice.
Snake eyes - two 1s, a total of 2.
Boxcars - two 6s, a total of 12.
Yo / yo-leven - the number 11 (said this way so it isn't confused with "seven").
Hardway - rolling a pair to make 4, 6, 8, or 10 (e.g., 3-3 is a "hard 6"). (Hardways.)
Odds bet - the 0% house-edge bet you can place behind a Pass Line once a point is set. (Odds bet.)
Blackjack terms
Hit / Stand - take another card, or keep your hand.
Double down - double your bet and take exactly one more card. (When to double.)
Split - turn a pair into two separate hands with two bets.
Surrender - forfeit half your bet to fold a bad hand.
Bust - go over 21 and lose automatically.
Push - a tie with the dealer; your bet is returned.
Natural / blackjack - an Ace plus a 10-value card on the first two cards, normally paying 3:2. (3:2 vs 6:5.)
Soft hand - a hand with an Ace counted as 11 (can't bust on the next card); a hard hand has no such Ace.
Insurance - a side bet that the dealer has blackjack; a bad bet. (Why to decline it.)
DAS - "double after split," a player-friendly rule allowing a double on a split hand.
Roulette & baccarat terms
Inside bets - roulette bets on specific numbers (straight, split, street, corner) with long odds.
Outside bets - roulette bets on big groups (red/black, odd/even, dozens, columns).
Straight up - a single-number roulette bet, paying 35:1.
Single zero / double zero - European wheels have one 0 (2.70% edge); American wheels add 00 (5.26%). (Compare them.)
Banker / Player / Tie - the three baccarat bets. Banker is the best at 1.06%. (Banker vs Player.)
Natural (baccarat) - a two-card total of 8 or 9, which usually ends the hand.
Roads - the scoreboards tracking past baccarat results; fun to watch, useless for prediction.
Poker terms
Video poker - a machine game of five-card draw against a paytable (no dealer). Full-pay machines are among the best bets in the casino. (Video poker trainer.)
Jacks or Better - the most common video poker game; the smallest paying hand is a pair of Jacks. A "9/6" machine (full house pays 9, flush pays 6) returns 99.54% with perfect play.
Paytable - the printed schedule of what each hand pays. On video poker it's the whole game — check the full-house and flush rows, since 9/6 and 8/5 machines look identical but pay very differently.
Hold / Draw - in video poker you hold the cards you keep, then draw replacements for the rest. Choosing the right hold every hand is the entire skill.
Royal flush - A-K-Q-J-10 of one suit, the top hand. At max coins it pays an 800-for-1 jackpot, which is why you always bet 5 coins.
Ante / Play - in Three Card Poker, the Ante is your opening bet; after seeing your cards you either make an equal Play bet or fold. (Three Card Poker trainer.)
Ante Bonus - a Three Card Poker bonus paid on a straight or better regardless of the dealer (straight 1:1, trips 4:1, straight flush 5:1).
Pair Plus - an optional Three Card Poker side bet that pays on a pair or better in your own three cards (2.32% house edge).
Element of risk - house edge measured per dollar actually wagered (including the Play bet), the figure that compares fairly across games. Three Card Poker is ~2% by this measure.