Half of gambling literacy is vocabulary — sites, streamers and Discord chats throw around terms that quietly determine whether you understand what you’re signing up for. This is the reference we wish existed when we started: plain definitions, no filler. Bookmark it.
Money & bonuses
- Rakeback — percentage of the house edge returned on every bet, win or lose. The most honest bonus type.
- Lossback / cashback — percentage of net losses returned over a period. Insurance, not income.
- Wagering requirement — how many times you must bet a bonus before withdrawing it. 40x on $100 = $4,000 of bets. Run it through the wagering calculator.
- Sticky bonus — your deposit is locked behind the bonus wagering. Non-sticky — real money plays first, bonus can be forfeited. Huge difference.
- Rain — free balance dropped in chat, split among active users.
- Faucet — tiny free balance claims on a timer; for testing games, not income.
- Reload — a deposit bonus for existing players.
- Max bet rule — betting above a limit while a bonus is active voids it. Usually ~$5.
House math
- House edge — the casino’s average cut of every bet. 1% edge = $1 per $100 wagered, long-run.
- RTP — Return to Player; 100% minus the house edge. A 96% slot keeps 4%.
- Volatility / variance — how swingy a game is. High variance = long droughts, big spikes.
- Expected value (EV) — what a bet returns on average. All casino games are negative EV; the question is how negative.
- Bankroll — money dedicated to gambling, separate from money you need.
- Tilt — emotional play after losses. The most expensive bug in the human casino player.
Fairness tech
- Provably fair — cryptographic scheme letting you verify each round wasn’t manipulated. See our explainer.
- Server seed — the casino’s secret value, hashed and shown before the round, revealed after.
- Client seed — your contribution to the randomness; rotate it regularly.
- Nonce — the round counter that makes every result unique.
- Hash — the one-way fingerprint of the server seed; proof it was fixed before you bet.
- Verifier — a tool that recomputes results from seeds. Ours: Provably Fair Verifier.
- RNG — Random Number Generator; the traditional, lab-certified fairness model. Comparison: RNG vs provably fair.
Skin economy
- Trim / conversion cut — the 5–15% discount sites apply when pricing skin deposits.
- Float — a skin’s wear value (0–1), affecting look and price.
- Trade hold — Steam’s delay on trades without mobile authenticator.
- API key scam — hijacking your Steam Web API key to redirect your trades. Defense: security guide.
- Case battle — players open identical cases; highest total value takes all.
- Upgrader — bet an item for a chance at a better one, odds scaled by value difference.
Game types
- Crash — multiplier climbs until it busts; cash out before it does. See crash sites.
- Dice — pick a win chance, payout scales inversely, ~1% edge. Guide.
- Plinko — ball drops through pegs into payout slots. Guide.
- Mines — reveal tiles, avoid bombs, cash out anytime. Guide.
- Limbo — pick a target multiplier, win if the round beats it. Strategy guide.
- Coinflip — 50/50 duel for skins. Guide.
- Jackpot — everyone deposits into a pot; one ticket wins all, odds proportional to stake.
Site vocabulary
- KYC — Know Your Customer identity checks. Sites without it: no-KYC list.
- Exit scam — a site closing with user balances. Victims in our Site Graveyard.
- Rake — the commission on PvP games like coinflip pots.
- Whale — a very high-volume player. VIP programs exist for them; the rest of us get the public tier. See VIP programs explained.
Anything missing that you keep seeing in chats? The concepts behind most of these terms get the long-form treatment across our free tools and guides — start with how we rank sites to see which of these terms actually move a rating.