Gomoku Glossary: Complete A-Z of Terms and Definitions
A glossary for common Gomoku and Renju terms, from basic shapes to formal Renju terminology. Definitions identify where a term is a casual teaching shortcut and where the official rules control. Check the linked rules source before using a simplified diagram to adjudicate a tournament game.
10 Must-Know Terms
If you are new to gomoku, start here. These ten concepts cover roughly 80% of what you need to understand the game and follow strategy guides.
A–Z Index
Shapes & Patterns
The fundamental stone configurations — the vocabulary of every gomoku position.
Open Two 活二 · 活二
Two stones in a row with both ends open. The foundational building block — weak on its own, but it can develop into an open three, so strong players create and combines them to build pressure.
Open Three 活三 · 活三
Three stones in a row with both ends open. It can become an open four on the next move, so the opponent must respond immediately or lose. One of the most important forcing shapes.
The red-ringed stone is the move that creates the shape.
Open Four 活四 · 活四
Four stones in a row with both ends open. Unblockable — the opponent can cover only one end, so you complete five on the other. An open four is a winning threat.
The red-ringed stone is the move that creates the shape.
Closed Three 眠三 · 眠三
Three in a row with one or both ends blocked. Less flexible than an open three and slower to develop, but it can still become a closed four and create forcing threats.
Closed Four 冲四 · 冲四
Four in a row with one end blocked. Still a forcing move (the opponent must block the open end), but easier to defend than an open four since there is only one winning point to cover.
The red-ringed stone is the move that creates the shape.
Overline 长连 · 長連
A line of six or more stones. This site’s casual exact-five game does not count it as a win; free-style can count it as a win; formal Renju treats a Black overline as forbidden and a White overline as a win.
The red-ringed stone is the move that creates the shape.
Double-Three 双三 · 三三
A move that creates more than one qualifying three from the placed stone. Formal Renju determines whether a Black double-three is forbidden through detailed definitions and exceptions, so a simple diagram is only an introduction.
The red-ringed stone is the move that creates the shape.
Double-Four 双四 · 四四
A move that creates more than one qualifying four from the placed stone. It is forbidden for Black under formal Renju; the exact classification follows the official rules.
The red-ringed stone is the move that creates the shape.
Four-Three 四三 · 四三
A move that creates a four and a three at the same time. Its tactical value and legality depend on the board position and rule set, especially in formal Renju.
The red-ringed stone is the move that creates the shape.
Split Three 跳三 · 跳び三
Three stones with a gap (such as X-XX or XX-X) that can still become an open four by filling the gap. It functions like an open three — the opponent must respond or be overrun.
Empty Triangle 空三角 · 空き三角
Three stones forming a triangle with one empty intersection in the middle. An inefficient shape that wastes a stone; generally avoided because the same stones in a line would be stronger.
Five in a Row (pattern) 五连 · 五連
The winning pattern: an unbroken line of exactly five stones, horizontal, vertical, or diagonal. Not six, not four — exactly five. The entire object of the game.
The red-ringed stone is the move that creates the shape.
Tactics
How shapes combine into plans: forcing sequences, calculation, and the double threat.
Forcing Move 先手 · 先手
A move the opponent must respond to immediately — typically a four (which threatens five) or an open three (which threatens an open four). Forcing moves let you control the tempo and build winning sequences.
VCF 连续冲四胜 · 連続四
Victory by Continuous Four — a sequence of forcing fours that leads to an unavoidable win. Calculating VCFs deep into the game tree is a core intermediate skill and the most common way games are won at club level.
VCT 连续活三胜 · 連続三
Victory by Continuous Threat — like VCF but using open threes as the primary weapon. Harder to calculate than VCF because open threes offer the opponent more defensive choices.
Double Threat / Fork 双打 · 両狙い
A move that creates two threats at once, so the opponent can block only one. The basis of most winning combinations — double-threes, double-fours, and four-threes are all forms of double threat.
Tempo 步调 · 手番
The initiative — having the opponent respond to your moves rather than pursue their own plan. Gaining tempo means dictating the sequence, which is usually decisive.
Setup Move 做杀 · 待ち手
A quiet move that prepares a future forcing sequence without creating an immediate threat. Setup moves are how strong players convert a positional edge into a calculable win.
Threat Tree 威胁树 · 読み
The branching sequence of forcing moves and opponent responses a player calculates mentally. Building and evaluating threat trees is the core of gomoku calculation.
Block 挡 · 受け
A defensive move that stops the opponent’s line from extending. The fundamental defensive response — but against a double threat, a single block is not enough.
Openings
The structured first moves of tournament Renju and the rules that govern them.
Direct Opening 直指 · 直指
One of the two opening families named in the RIF rules. The official opening section lists 13 direct patterns; consult the current source for their diagrams and procedure.
Indirect Opening 斜指 · 斜指
One of the two opening families named in the RIF rules. The official opening section lists 13 indirect patterns; consult the current source for their diagrams and procedure.
Swap2 交换2 · スワップ2
A named swap-style opening format used in some Renju contexts. It is not interchangeable with every RIF opening procedure or every event’s regulations.
26 Designated Openings 26种开局 · 26の珠
The 13 direct and 13 indirect patterns shown in the current RIF rules. They belong to that formal procedure and do not automatically apply to casual Gomoku or every tournament format.
Center (H8) 天元 · 天元
The center intersection on a 15×15 board. It is a practical default for casual play because it leaves space in every direction, while formal events follow their specified opening procedure.
Star Point 星位 · 星
A marked reference point on the board. In gomoku the center star (H8) is the conventional opening move; on larger Go boards star points mark handicap and reference positions.
Rules & Variants
Standard gomoku, Renju, and free-style — and the rules that distinguish them.
Casual Exact-Five Rules 标准规则 · 標準ルール
The house rules used by this site’s browser game: 9×9, 13×13, or 15×15 board; exactly five in a row wins; no Renju forbidden-move enforcement. Other apps and groups may use different rules.
Renju 连珠 · 連珠
The professional variant of gomoku, formalized in Japan in 1899. The name means "connected pearls." Renju forbids Black from making double-threes, double-fours, and overlines to counter Black’s first-move advantage.
Free-Style 自由式 · フリースタイル
A five-in-a-row variant in which an overline can count as a win. Confirm the host’s rules because free-style implementations can vary.
Forbidden Moves 禁手 · 禁手
In formal Renju, Black is subject to rules on overlines, double-fours, and double-threes. The current RIF rules include detailed definitions and exceptions; use them rather than a simplified pattern label to adjudicate a game.
Overline Rule 长连禁手 · 長連禁手
In formal Renju, an overline is forbidden for Black, while a White overline counts as a win. Casual exact-five and free-style rules handle the same shape differently.
Exactly-Five Win 恰好五子 · 五連勝
A win condition used by this site’s casual game: an unbroken line of exactly five stones. Formal Renju applies color-specific rules for overlines, while free-style can count six or more.
Draw 和局 · 引き分け
When the board fills up without either player making five in a row. Rare in casual play but possible, especially between defensive players on a full 15×15 board.
RIF 国际连珠联盟 · 国際連珠連盟
The Renju International Federation. Its website publishes International Rules of Renju and event-related materials. Consult the current rule text and specific event regulations for competition requirements.
Intersection 交叉点 · 交点
The point where two grid lines cross. Stones are placed on intersections (as in Go), not inside the squares. A 15×15 board has 225 intersections.
General & History
The game’s names, history, and the math and AI behind it.
Gomoku 五目並べ · 五目並べ
The Japanese name for the game, meaning "five points in a row," and the most common English name. Also called Five in a Row, Gobang, Omok (오목, Korean), and Wuzi Qi (五子棋, Chinese).
Gobang 碁盤 · 碁盤
An older English name for the game, derived from "goban," the Japanese word for the board. Largely replaced by "gomoku" in modern usage but still appears in older books and some regions.
Omok 오목 (韩) · —
The Korean name, meaning "five pebbles." Gomoku is widely played in Korea, with a competitive scene that overlaps with Renju but often uses slightly different overline rules.
Wuzi Qi 五子棋 · 五子棋
The Chinese name, "five-stone chess." Gomoku has been played in China for centuries, and modern Chinese players are among the strongest in international Renju.
Kakugo 格五 · 格五
A Heian-period (794–1185) Japanese name for an early form of the game. One of the oldest recorded references to five-in-a-row play in Japan.
Piškvorky — · —
The Czech and Slovak name for the game. Gomoku has a strong historical following in Central Europe, and the region has produced world-class Renju players.
Victor Allis 维克托·阿利斯 · ビクター・アリス
A computer-science researcher whose early-1990s work described threat-space search for Go-Moku and documented a first-player win for a defined unrestricted 15×15 setting. The result should not be generalized to every rule set.
Solved Game 已解博弈 · 解明済みゲーム
A game with a mathematically established outcome under a specified model. A published first-player-win result exists for a defined unrestricted Gomoku setting; this site has not found an equivalent published result for standard Renju.
Minimax + Alpha-Beta 极大极小+剪枝 · ミニマックス+αβ
The search algorithm most gomoku AIs use to choose moves: explore the move tree to a fixed depth, assume the opponent plays best, and prune branches that cannot improve the result. The engine on this site uses it.
Black / White Stones 黑子/白子 · 黒石/白石
The two sides. Black always moves first — a significant advantage, which is why Renju restricts Black. Traditionally played with Go stones on a Go board.
Go Board 围棋盘 · 碁盤
The traditional equipment: a wooden grid of intersections shared with Go. A 15×15 grid is standard for gomoku (Go uses 19×19), but the board and stones are the same.
Trilingual Term Comparison
Gomoku has deep roots across East Asia, so most key terms have Chinese and Japanese forms. This table collects the most important ones.
| English | 中文 (Chinese) | 日本語 (Japanese) |
|---|---|---|
| Gomoku | 五目並べ | 五目並べ |
| Five in a Row | 五连 | 五連 |
| Renju | 连珠 | 連珠 |
| Open Three | 活三 | 活三 |
| Open Four | 活四 | 活四 |
| Closed Four | 冲四 | 冲四 |
| Double-Three | 双三 | 三三 |
| Double-Four | 双四 | 四四 |
| Overline | 长连 | 長連 |
| Forbidden Move | 禁手 | 禁手 |
| VCF | 连续冲四 | 連続四 |
| Center (H8) | 天元 | 天元 |