Poker glossary
The full vocabulary of online poker, from 3-bet to zerg.
- 3-bet
- The second re-raise preflop. The opener is the 1-bet, the re-raise is the 3-bet (because the big blind counts as 1).
- 4-bet
- The re-re-raise. Often a polarised range, value hands plus bluffs, no middling holdings.
- Bumhunting
- Sitting only with weaker players and refusing to play when only competent regs are at the table. Disabled by anonymous-table sites like Bovada and Ignition.
- Cooler
- A spot where two strong hands collide and one loses big, KK vs AA, set over set. Bad luck, not bad play.
- Coin flip
- Pair vs two overcards, roughly 55/45. The "race" spot that defines every tournament.
- Donk bet
- Leading into the previous-street aggressor out of position. Historically pejorative; modern theory has rehabilitated it in specific spots.
- Equity
- Your share of the pot at showdown, on average. Calculated by running every possible runout.
- EV (expected value)
- The average return of a decision across every possible outcome, weighted by probability.
- Fish
- A losing recreational player. The reason online poker is still viable in 2026.
- GTO
- Game-theory optimal, a strategy that cannot be exploited by any opponent. Solved approximately for hold'em via solvers.
- HUD
- Heads-up display. Real-time statistical overlay showing opponent tendencies. Banned on GGPoker, Bovada, WPT Global; allowed on PokerStars and Winning Network.
- ICM
- Independent Chip Model. Converts tournament chip stacks into dollar equities. See ICM explained.
- Limp
- Calling the big blind preflop without raising. Historically weak; the modern solver recommends it in some spots from the small blind and button.
- M-ratio
- Stack divided by cost of one orbit. The Harrington stack-depth metric. Use the calculator.
- Nit
- An over-tight player who only enters pots with premium hands.
- Polarised range
- A range that contains only very strong hands and bluffs, with no middling hands, used in 4-bet and large river-bet spots.
- Pot odds
- The price the pot is offering you on a call, expressed as a ratio. Use the calculator.
- Rake
- The percentage the room takes from each pot. Universal 5% on major sites, capped per stake. See the comparison.
- Rakeback
- The portion of rake the room pays back to active players, either flat or via loyalty programs.
- Reg
- A regular player. Skilled, profitable, recognisable on the daily player pool.
- ROI
- Return on investment, expressed as a percentage of buy-ins. The MTT equivalent of bb/100.
- Run it twice
- Dealing the remaining cards twice when all-in, each for half the pot, to reduce variance.
- Variance
- The randomness around your true win rate. See variance explained.
- Zerg
- Coordinated attack by multiple players against one, coined in poker for soft-collusion in cash games.