Fluorescent/fləˈresnt/ Definition 1 of 3Pro Tip 1/3Not Natural Light Fluorescent light comes from bulbs, not the sun or fire. Office buildings often use fluorescent lighting. Pro Tip 2/3Energy Efficient Fluorescent lights are popular because they save energy compared to regular bulbs. She installed fluorescent bulbs to reduce her electricity bill. Pro Tip 3/3Harsh Glow Some people find the light from fluorescents too bright or harsh. He dislikes the fluorescent glare in hospital corridors.