1、Solid state device embodying a p-n junction, emitting optical radiation when excited by an electric current[IEC62031-2008, Def. 3.1] [IEC60050 IEV 845-04-40]
2、a PN junction semiconductor device that, by spontaneous emission, emits incoherent optical radiation by injecting electrons and/or holes across the PN junction [IEC60050 IEV 731-06-04]
application of light to a scene, objects or their surroundings so that they may be seen Note – This term is also used colloquially with the meaning "lighting system" or "lighting installation".[IEC 60050, 845-09-01]