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English definition of “light”

light

noun [C/U] (ENERGY)   /lɑɪt/
the energy from the sun or fire and from electrical devices that allows you to see clearly : [U] Light was streaming through the windows . [U] The light was so bright that it hurt my eyes . A light is also anything that provides light, esp . an electric lamp : [C] Don’t forget to turn off the lights when you leave . A light is also a traffic light: Let’s go – you’ve got a green light.
(Definition of light noun (ENERGY) from the Cambridge Academic Content Dictionary © Cambridge University Press)
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