noun
double-sided wait; two-sided wait
In mahjong, a wait for one of two different tiles to complete a sequence (chow) and finish the hand. The two possible tiles are on opposite sides of a consecutive run, e.g., holding 4-5 and waiting for 3 or 6.
リャンメン待ちでテンパイした。
I reached tenpai with a double-sided wait.
リャンメン待ちは待ち牌が多いので有利だ。
A double-sided wait is advantageous because it has many winning tiles.
A wait for a single tile to complete a sequence at the edge (e.g., 1-2 waiting for 3). リャンメン待ち waits for two tiles, while ペンチャン待ち waits for only one.
A wait for a single tile to fill the middle of a sequence (e.g., 4-6 waiting for 5). Like ペンチャン待ち, it waits for only one tile, unlike the two-tile wait of リャンメン待ち.
A wait for either of two pairs to become a triplet. リャンメン待ち completes a sequence, while シャンポン待ち completes a triplet.
From リャンメン (ryammen, 'both sides', from Chinese 两面) + 待ち (machi, 'wait'). A mahjong term describing a wait that can be completed by two different tiles.