Saint Elmo's fire

noun

Saint El·​mo's fire ˈsānt-ˈel-(ˌ)mōz- 

variants or St. Elmo's fire or less commonly Saint Elmo's light or St. Elmo's light

: a flaming phenomenon sometimes seen in stormy weather at prominent points on an airplane or ship and on land that is of the nature of a brush discharge of electricity

Word History

Etymology

St. Elmo (Erasmus) †303 Italian bishop & patron saint of sailors

First Known Use

1753, in the meaning defined above