lumen
/ˈluːmən/
noun
- The inside space of a tube-shaped structure in the body, such as a blood vessel or intestine.
- Doctors use a scope to look inside the lumen of the colon.
- The lumen of an artery can become narrowed by plaque buildup.
- Food passes through the lumen of the digestive tract.
- A unit of measurement for the total amount of visible light emitted by a source.
- A higher lumen rating means a brighter flashlight.
- The projector needs at least 3000 lumens for a clear image in a large room.
- This light bulb produces 800 lumens of brightness.