levin \LEV-in\ (noun) - Lightning; a bright light.
"Broad and frequent through the night
Flash'd the sheets of levin-light;"
Walter Scott; The Dance of Death; 1815.
From Middle English levene. Ultimately from Indo-European root leuk- (light) that's resulted in other words such as lunar, lunatic, light, lightning, lucid, illuminate, illustrate, translucent, lux, and lynx,