|—n , pl -mens, -mina|
|1.||lm the derived SI unit of luminous flux; the flux emitted in a solid angle of 1 steradian by a point source having a uniform intensity of 1 candela|
|2.||anatomy a passage, duct, or cavity in a tubular organ|
|3.||a cavity within a plant cell enclosed by the cell walls|
|[C19: New Latin, from Latin: light, aperture]|
lumen lu·men (lōō'mən)
n. pl. lumens or lu·mi·na (-mə-nə)
The inner open space or cavity of a tubular organ, as of a blood vessel.
The unit of luminous flux in the International System of Units, that is equal to the amount of light given out through a solid angle by a source of one candela intensity radiating equally in all directions.
|lumen (l'mən) Pronunciation Key
Plural lumens or lumina