the.com/ball lightning

means A rare, poorly understood glowing sphere—often grapefruit to beach-ball sized—that appears during thunderstorms and drifts, hovers, or vanishes within seconds, sometimes passing through walls or windows.

from The term is purely descriptive, pairing 'ball' (its shape) with 'lightning' (its storm-linked origin), and dates to attempts by scientists and witnesses to name a phenomenon reported for centuries but never satisfactorily explained. Sightings go back hundreds of years in folklore and ship logs, but because the glowing orbs are rare, brief, and impossible to summon in a lab, no single physical theory—plasma, vaporized silicon, ball-shaped electrical discharge—has been confirmed. The name itself is honest about that mystery: it describes what people see, not what it actually is.