W138 glossary: the words behind the rules
Why a glossary
Most disputes with casino support come from a word read in two different ways: "rollover", "net loss" or "valid bet". These definitions follow how W138 itself uses the terms in its promotion and banking rules, so you can read an offer and know exactly what it asks.
Terms A to Z by topic
| Term | Meaning |
|---|---|
| Rollover | The amount to wager before a bonus can be withdrawn; at W138 usually (deposit + bonus) × the multiplier. |
| Turnover | The total of your valid bets in a period, win or lose. |
| Valid bet | A settled bet that counts: draws, voids, both-side bets and odds below 1.50 do not. |
| Net loss | Win/loss minus rebates and bonuses received, used for VIP cashback. |
| Rebate | Daily return on turnover: live 0.8%, slots 0.4%, sports 0.3%. |
| Cashback | Money back based on losses, such as the slot cashback or VIP cashback. |
| Reload bonus | A bonus on deposits after the first. |
| Welcome bonus | The single first-deposit bonus for new members. |
| Main wallet | Your central MYR balance. |
| Club wallet | A separate balance inside Mega888 or similar clubs. |
| Product | A lobby category; rollover counts in one product only. |
| RTP | Return to player, the long-run payback of a slot. |
| House edge | The casino's long-run margin, 100% minus RTP. |
| Volatility | How unevenly a slot pays out. |
| Feature buy | Paying to enter a slot's bonus round directly. |
| Hall | A live dealer studio, for example AB Hall. |
| Banker / Player | The main baccarat bets (0.95:1 and 1:1). |
| Road map | A record of past baccarat results; not a prediction. |
| Squeeze | Slow card reveal; no effect on the outcome. |
| Bid baccarat | A variant where players bid to reveal the cards. |
| Asian handicap | A goal head start that removes the draw. |
| Quarter line | A line like 2.25 that splits the stake in two. |
| Over/under | Total goals or points above or below a line. |
| 1X2 | Home, draw or away over regular time. |
| Mix parlay | Several legs in one ticket; all must win. |
| Malay odds | Asian odds format with negative prices. |
| Decimal odds | Return per unit including stake, used in W138 rules. |
| In-play | Betting during a match. |
| Void | A cancelled, refunded bet. |
| Big bet (4D) | Wins on all 23 prize numbers at lower payouts. |
| Small bet (4D) | Wins only on the top three prizes at higher payouts. |
| Box / iBox | 4D bets that cover every order of the digits. |
| KYC | Identity checks before payouts. |
| Self-exclusion | Blocking your own account for a set time. |
| Bet slip ID | The ticket number used to claim bet-based offers. |
| Organisational account | Several accounts run by one person or group; voids bonuses. |
Each lobby guide explains these terms in context: slots, live casino, sportsbook, 4D and promotions.
Frequently asked questions
What is the difference between rebate and cashback?
A rebate is paid on everything you wager, win or lose. Cashback is paid only on losses and usually needs a claim.
Why do bets below 1.50 odds not count?
Very low odds are close to a sure result. Excluding them stops players clearing rollover with almost no risk.
Is RTP the same on every casino?
Not always. Some studios offer the same game in several RTP versions. The figure shown inside the game info screen is the one that applies.
