American Mahjong has its own vocabulary, and a lot of it doesn’t map directly onto other Mahjong variants. Here are the terms you’ll hear most often at the table, explained in plain language.
Core terms
Joker
A wild tile that can substitute for almost any tile in an exposed set. American sets include 8 jokers — more than most other Mahjong traditions — but certain hands on the NMJL Card don’t allow jokers at all, so you always need to check.
Exposure / Exposed
A set of tiles (a Pung, Kong, or Quint) that you’ve called from another player’s discard and laid face-up in front of your rack. Once exposed, that set is visible to everyone and generally locks in part of your hand. See concealed vs. exposed hands for the strategic trade-offs.
Concealed Hand
A hand built entirely from tiles you drew yourself, with no exposures called from other players. Concealed hands are usually worth more and, on some card hands, are required — see our full breakdown.
Pung, Kong, and Quint
A Pung is three matching tiles, a Kong is four, and a Quint is five — Quints are only possible because jokers let you extend a set beyond four tiles, which doesn’t exist in most other Mahjong variants.
The Charleston
The mandatory (plus optional second-round) tile-passing phase that happens before play starts, meant to give everyone a chance to improve their hand before the first discard. See our full Charleston guide.
The Wall
The stacked tiles built by each player at the start of the hand, pushed together into a square that players draw from during play. See table setup for how the wall gets built.
Wall Game
What happens when the wall runs out of tiles before anyone completes a hand — the round ends without a winner and a new hand is dealt. More on this in how a hand ends.
Dead Hand
A hand that’s been disqualified, usually because of a tile-count error or an invalid exposure, and can no longer win that round even if it’s otherwise complete.
Flowers
A separate group of 8 tiles used differently depending on the hand you’re building; some hands require them, others don’t use them at all.
Soap
A common nickname for the White Dragon tile, since its blank face resembles a bar of soap.
Charleston-specific terms
Blind Pass
A pass made during specific points in the Charleston when a player doesn’t have three tiles they’re willing to give up. Instead, they pass along tiles they just received, without looking at them first. Blind passes are only allowed during certain passes of the Charleston, not all of them — see exactly when.
Courtesy Pass
An optional, mutually agreed exchange of zero to three tiles between the two players seated across from each other, offered after the main Charleston passes are complete. Unlike the main Charleston, it’s optional for both players and widely treated as table custom. Full details in our blind pass and courtesy pass guide.
Card structure terms
The NMJL Card organizes its hands into named categories that repeat, in some form, from year to year, even though the specific hands within them change annually. You’ll commonly hear players refer to categories generically as things like Consecutive Run hands, 2468 hands (built from even numbers), Winds-Dragons hands, and Singles and Pairs hands. We’re describing these as structural categories here, not reproducing any specific year’s actual hand list — for the full breakdown, see NMJL Card categories, explained.
Standard Hand vs. Card Hand
Some tables and older references distinguish a small set of standard, unchanging hand shapes from the annually-updated Card hands, though the overwhelming majority of American Mahjong today is played strictly from the current year’s Card.
Frequently Asked Questions
What’s the difference between a Pung and a Kong?
A Pung is three of the same tile; a Kong is four. Both can be called from a discard or, less commonly, drawn.
Why do some hands say ‘no jokers’?
Certain categories on the NMJL Card, like Singles and Pairs hands, are designed to be harder and specifically exclude jokers as a way of balancing difficulty and scoring.
What does it mean when a hand needs to be ‘concealed’?
It means you can’t have called any exposures (Pungs, Kongs, or Quints) from other players’ discards during the hand — every tile has to come from your own draws.
Is ‘Soap’ an official term?
No — it’s table slang for the White Dragon, not an official NMJL term, but you’ll hear it constantly at most tables.
Terms you’ll hear less often but should still recognize
Dead Wall / Wall Game
Not to be confused with the “dead hand” of an individual player, a wall game refers to the whole round ending because the shared wall of tiles ran out before anyone completed a hand. Some players use “dead wall” loosely to mean the same thing, though it isn’t a formally separate structure the way it is in some other Mahjong traditions.
Rack
Both the physical sloped tray you keep your tiles on and, informally, shorthand for “your hand” — as in, “what’s on your rack.” See our racks and pushers guide for what to look for when buying one.
Exposure Slot
Table slang some players use for the area in front of their rack where exposed Pungs, Kongs, and Quints get laid down, distinct from the concealed tiles still hidden behind the pusher.
Why the vocabulary matters more than it seems
A lot of first-time players find the terminology more intimidating than the actual mechanics, mostly because so many terms get used in rapid conversation at the table without anyone pausing to define them. Once you’ve got Pung, Kong, exposure, concealed, and the Charleston-specific terms down, the rest of the vocabulary tends to click quickly, since most of it is just describing variations on those same core ideas.
It also helps to just ask. Most American Mahjong groups, especially ones that welcome newer players, expect a certain amount of “wait, what does that mean” during someone’s first few sessions, and answering those questions is part of the social fabric of the game rather than an interruption to it.
Keep a running mental list of the terms that trip you up most and revisit this glossary between sessions rather than trying to absorb everything in one sitting. Most players find that two or three real hands with a patient table teach the vocabulary faster than any amount of reading alone.
Want the full walkthrough these terms fit into? Read the beginner’s guide →
