1. a glass bulb containing a wire filament or other light source that produces light when electricity passes through it

Examples

• The lightbulb in the kitchen burned out.
• She screwed in a new LED lightbulb.
• The lightbulb flickered before going dark.
• He had a lightbulb moment and solved the problem.
• Energy-efficient lightbulbs last much longer.
• The old incandescent lightbulb was very hot to touch.