many-sided wait; complex wait
In mahjong, a hand that is waiting for three or more different tile types to complete. A technical term used in strategy discussions.
from Chinese duōmiàn zhāng
If you learn the shapes of many-sided waits, your waits become wider and it becomes easier to win.
This hand is a many-sided wait; you can win with three types of tiles.
多面待ち is a synonymous term also meaning 'many-sided wait', but 多面張 is the more common technical term.
From Chinese 多面張 / 多面张 (duōmiàn zhāng), literally 'many-sided wait'. The reading タメンチャン reflects the Chinese pronunciation adapted into Japanese mahjong terminology.