flash of lightning; flash of a sword; brandishing a sword
A yojijukugo describing a sudden, brilliant flash, originally of lightning, and by extension the swift, bright arc of a sword being drawn or swung. Often used in literary or dramatic contexts.
A flash of lightning, and then thunder roared.
With a flash of his sword, he cut down the enemy.
A yojijukugo composed of 紫 (purple), 電 (lightning), 一 (one), and 閃 (flash). The exact origin is uncertain, but it evokes the image of a single, brilliant purple flash of lightning, later applied to swordplay.