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sword; blade
single stroke
名匠が鍛えた一刀が宝物として伝わる。
A sword forged by a master smith is handed down as a treasure.
侍は一刀のもとに敵を斬り伏せた。
The samurai cut down the enemy with a single stroke.
一刀両断の決断が求められた場面だった。
It was a situation that called for a decisive judgment.