Glossary

Common terminology used in mahjong tile efficiency training.

Basic Concepts

Tenpai (Ready Hand)

A hand that has completed 4 sets + 1 pair combination and only needs one more tile to win.

Example 1: Two-sided Wait

This hand is waiting for 4p or 7p, a typical two-sided wait.

Breakdown: m123, m456, m789 (3 sequences), s88 (pair), p56 (taatsu)

Example 2: Single Wait

This hand is waiting for 9p, a single wait.

Breakdown: m111, m222, m333 (3 triplets), p123 (sequence), p9 (single tile)

Example 3: Three-sided Wait

This hand is waiting for 1m, 4m, or 7m, a three-sided wait.

Breakdown: m234 (sequence) + m56 (taatsu, waits 4, 7), or m23 (taatsu, waits 1, 4) + m456 (sequence); p123, s123 (2 sequences), p99 (pair)

Heqie (Discard Decision)

The process of deciding which tile to discard from a 14-tile hand.

Example: Optimal Discard

Discard 1s because it's isolated and doesn't help the hand structure.

After discarding 1s, hand becomes ready (waiting for 1p or 4p) with maximum efficiency.

Shape Terms

Meld (Set)

A group of three tiles in a winning hand, either a sequence or a triplet. The standard hand has 4 melds + 1 pair.

Head (Pair)

A pair of identical tiles required in the winning hand, also called "eyes" or "head" (将 jiàng).

Example: Head

Two 9m form a head (pair), essential in winning hand structure.

Sequence (Shuntsu)

Three consecutive tiles of the same suit, like m123 or p456.

Example: Sequence

Character sequence: 1-2-3

Dot sequence: 4-5-6

Triplet (Koutsu)

Three identical tiles, like m111 or p555.

Example: Triplet

Triplet: Three 1 Characters

Triplet: Three 5 Dots

Taatsu (Incomplete Sequence)

An incomplete sequence combination, including:

Two-sided taatsu: like 45, can wait for 3 or 6
Middle taatsu: like 46, can only wait for 5
Edge taatsu: like 12, can only wait for 3

Example 1: Two-sided Taatsu

Two-sided taatsu: 4p-5p, can wait for 3p or 6p, high efficiency.

Example 2: Middle Taatsu

Middle taatsu: 4p-6p, can only wait for 5p, lower efficiency.

Example 3: Edge Taatsu

Edge taatsu: 1p-2p, can only wait for 3p, lowest efficiency.

Shanten Related

Shanten Number

Indicates how many steps (effective draws) away from tenpai. Lower is better.

0 shanten = tenpai (ready)
1 shanten = one tile away from ready
2 shanten = two tiles away from ready
And so on

Example 1: 0 Shanten (Tenpai)

This hand has 0 shanten, already in tenpai, waiting for 4p or 7p.

Example 2: 1 Shanten

This hand has 1 shanten, one effective draw away from tenpai.

Example 3: 2 Shanten

This hand has 2 shanten, needs two effective draws to reach tenpai.

One Shanten

A state one effective tile away from tenpai, a key focus of tile efficiency training.

Example: One Shanten

This hand is one shanten. It has two taatsu (p23 and s23), drawing one tile that can form a sequence will make it tenpai.

Hand has: m123, m456, m789 (3 sequences), p23 (taatsu, waits 1, 4), s23 (taatsu, waits 1, 4), missing one set.

Effective Tiles

Tiles that can reduce the shanten number when drawn. For example, in one shanten state, all tile types that can make the hand ready.

Example: Effective Tiles

The effective tiles for this hand are p1, p2, p3, p4 and s1, s2, s3, s4 (8 types, 28 tiles). Drawing any of these tiles reduces the shanten count from 1 to 0, making the hand ready.

Improvement

Drawing a tile that improves hand state, including tiles that reduce shanten.

Special Hands

Chitoitsu (Seven Pairs)

A winning hand composed of 7 pairs, no sets needed.

Example: Chitoitsu

Composed of 7 different pairs. Note: requires 14 tiles (7 pairs × 2 tiles = 14 tiles).

Kokushi (Thirteen Orphans)

A special winning hand using all 13 terminal and honor tiles plus one pair.

Example: Kokushi

Contains: 1 and 9 of each numbered suit (m1, m9, p1, p9, s1, s9) + all 7 honor tiles (z1-z7), with one tile being a pair.

Regular Form (Standard Winning Hand)

The basic winning hand structure composed of 4 sets + 1 pair.

Example 1: Regular Form (All Sequences)

Composed of 4 sequences + 1 pair: m123, m456, m789, p123 (sequences), p99 (pair).

Example 2: Regular Form (Mixed)

Composed of 2 triplets + 2 sequences + 1 pair: m111, m222 (triplets), p456, s789 (sequences), s88 (pair).

Strategy Terms

Tile Efficiency

The ability to maximize improvement chances and tenpai speed through reasonable discards and keeps.

Good Shape

Hand shapes that are easy to improve with many waiting tiles.

Example: Good Shape

This hand is waiting for 4p or 7p, a two-sided wait, which is good shape.

Good shape characteristics: many waiting tiles, easy to improve, high winning probability.

Poor Shape

Hand shapes that are difficult to improve with few waiting tiles, such as single waits, middle waits, etc.

Example: Poor Shape

This hand is waiting for 9p, a single wait, which is poor shape.

Poor shape characteristics: few waiting tiles, difficult to improve, low winning probability.