lumen
[ loo-muhn ]
/ ˈlu mən /
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noun, plural lu·mens, lu·mi·na [loo-muh-nuh]. /ˈlu mə nə/.
Optics. the unit of luminous flux, equal to the luminous flux emitted in a unit solid angle by a point source of one candle intensity. Abbreviation: lm
Anatomy. the canal, duct, or cavity of a tubular organ.
Botany. (of a cell) the cavity that the cell walls enclose.
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Origin of lumen
1870–75; <New Latin, special uses of Latin lūmen (stem lūmin-) light, window
Words nearby lumen
lumbricide, lumbricoid, lumbricosis, lumbricus, lumbus, lumen, lumen-hour, lum-hat, Lumholtz's kangaroo, Lumière, Luminaire
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Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021
Example sentences from the Web for lumen
British Dictionary definitions for lumen
lumen
/ (ˈluːmɪn) /
noun plural -mens or -mina (-mɪnə)
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 candelaSymbol: lm
anatomy a passage, duct, or cavity in a tubular organ
a cavity within a plant cell enclosed by the cell walls
Derived forms of lumen
lumenal or luminal, adjectiveWord Origin for lumen
C19: New Latin, from Latin: light, aperture
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
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Medical definitions for lumen
lumen
[ lōō′mən ]
n. pl. lumens
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, equal to the amount of light given out through a solid angle by a source of one candela intensity radiating equally in all directions.
Other words from lumen
lu′men•al null adj.The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
Scientific definitions for lumen
lumen
[ lōō′mən ]
Plural lumens lumina
The central space within a tube-shaped body part or organ, such as a blood vessel or the intestine.
The SI derived unit used to measure the amount of light passing through a given area per second. One lumen is equal to the luminous flux passing per unit solid angle from a light source with a strength of one candela.
The American Heritage® Science Dictionary
Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.