Definition of jack light in English:

jack light

noun

North American
  • A portable light, especially one used for fishing at night.

    • ‘The spearing was conducted from row boats in 2 to 6 feet of water, by means of ordinary fish spears with illumination from jack-lights.’
    • ‘During the Qing Dynastyi1644 - 1911), the local peasants and fishermen often made and used ice lanterns as jack-lights during the winter months.’