lumen

[ loo-muhn ]

noun,plural lu·mens, lu·mi·na [loo-muh-nuh]. /ˈlu mə nə/.
  1. 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

  2. Anatomy. the canal, duct, or cavity of a tubular organ.

  1. Botany. (of a cell) the cavity that the cell walls enclose.

Origin of lumen

1
1870–75; <New Latin, special uses of Latin lūmen (stem lūmin-) light, window

Words Nearby lumen

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How to use lumen in a sentence

British Dictionary definitions for lumen

lumen

/ (ˈluːmɪn) /


nounplural -mens or -mina (-mɪnə)
  1. 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: Symbol: lm

  2. anatomy a passage, duct, or cavity in a tubular organ

  1. a cavity within a plant cell enclosed by the cell walls

Origin of lumen

1
C19: New Latin, from Latin: light, aperture

Derived forms of lumen

  • lumenal or luminal, adjective

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for lumen

lumen

[ lōōmən ]


Plural lumens lumina
  1. The central space within a tube-shaped body part or organ, such as a blood vessel or the intestine.

  2. 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.

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