舟ふな囲がこいMeanings1nounboat castleshogi›A shogi defensive formation where the king is protected by pieces arranged in a shape resembling a boat. Used in specific opening strategies.舟ふな囲がこいは、振ふり飛車びしゃ戦せん法ぽうでよく使つかわれる囲かこいの一ひとつです。The boat castle is one of the castles often used in ranging rook strategies.