also: ターはい
noun
having too many tiles in one's hand
Mahjong term for the illegal state of holding more tiles than allowed, usually due to a mistake in drawing or discarding.
from Chinese duō pái
多牌に気づかずにツモを続けてしまった。
I kept drawing tiles without noticing I had too many tiles in my hand.
多牌は反則なので、すぐに指摘された。
Having too many tiles is a foul, so I was called out immediately.
少牌 means having too few tiles, the opposite error.
From Chinese 多牌 (duō pái, 'many tiles'). The reading ターパイ reflects the Chinese pronunciation adapted into Japanese mahjong terminology.