concealed kong; declaring a concealed kong
In mahjong, the act of forming a kong (four identical tiles) entirely from tiles in one's hand, without having called any of them from discards. The set is kept concealed until declared.
from Chinese àngàng
See also: 槓
When declaring a concealed kong, you place the four tiles face down in a row.
彼は手牌に同じ牌が4枚あったので、暗槓した。
He had four identical tiles in his hand, so he made a concealed kong.
Standard kanji spelling for this mahjong term.
Katakana spelling is common in mahjong contexts, especially in rulebooks or casual writing.
From Chinese 暗槓 (àngàng), literally 'concealed kong'. The kanji 暗 means 'dark' or 'hidden', and 槓 is a mahjong-specific character for a kong (four-of-a-kind).