雷らい火か

noun

flash of lightning; lightning bolt

Refers to the visible flash or bolt of lightning itself. Often used in literary or descriptive contexts.

• 夜よ空ぞらに雷らい火かが走はしった。

  A flash of lightning streaked across the night sky.

noun

fire caused by lightning

Specifically a fire that starts when lightning strikes something. Less common than the first sense.

• 落らく雷らいによる雷らい火かで山やまが燃もえた。

  The mountain burned from a fire caused by lightning.