Electric lighting; lights powered by electricity (e.g., indoor lights, street lamps). An older kanji form is 電燈.
夜になると、電灯が次々と点く。
At night the electric lights come on one after another.
昔は村に電灯がなく、夜は真っ暗だった。
In the past the village had no electric lights and nights were pitch dark.
電灯の取り替えは感電に注意して行ってください。
Be careful of electric shock when replacing a light fixture.