noun
diagonal attachment; kosumi-tsuke
A Go term for a diagonal contact play, specifically a move that attaches to an opponent's stone diagonally. Often referred to by the Japanese name in English Go literature.
白がコスミツケを打った。
White played a diagonal attachment.
この局面ではコスミツケが急所だ。
In this position, the diagonal attachment is the vital point.
Compound of コスミ (kosumi, 'diagonal move') and ツケ (tsuke, 'attachment'), both Go terms.