noun
lumen
The open space inside a tube or vessel.
Blood flows through the lumen of the artery.
Etymology
Latin lumen could mean an opening that lets in light as well as light itself. Anatomy applies the opening sense to the inner channel of a tube or vessel.
More examples
- The narrowed lumen leaves less room for blood to pass.
- The diagram shows the lumen inside the hollow tube.
- Cells line the intestinal lumen, separating its contents from surrounding tissue.
Forms
lumen · lumens · lumina