| 释义 |
lu·men
\ˈlümə̇n\ noun
(plural lu·mi·na \-mənə\ ; also lumens)
Etymology: New Latin lumin-, lumen, from Latin, light, air well, opening
1. : the cavity or passageway of a tubular organ
< the lumen of a blood vessel or the intestine >
2. : the space enclosed by the walls of a cell and in a living cell occupied by the protoplast
3. : the bore of a tube (as of a hollow needle or catheter)
4. : a unit of luminous flux equal to the light emitted in a unit solid angle by a uniform point source of one candle |