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

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use lumen in a sentence

Sarah and Jennifer are soon trapped in the trunk of the Lumina.
The Stacks: The Searing Story of How Murder Stalked a Tiny New York Town|E. Jean Carroll|April 19, 2014|DAILY BEAST
Jamie Merisotis CEO, Lumina Foundation The president asked for ideas that would be immediately implementable.
How I'd Create Jobs|The Daily Beast|December 7, 2009|DAILY BEAST
Qui quociens dormit nunquam sua lumina claudit, T. Crederis esse leo vigilanti semper ocello, Ruodlieb iv.
Selections from Early Middle English 1130-1250: Part II: Notes|Various
Ad cœlum tendens ardentia lumina frustra,Lumina nam teneras arcebant vincula palmas.
The Lusiad|Lus de Cames

Omnia qui magni dispexit lumina mundi, Qui stellarum ortus comperit atque obitus.
Prometheus Bound and Seven Against Thebes|Aeschylus
In advanced stages there is much gummy material in the lumina, and even large cavities filled with this gum may be found.
Disease in Plants|H. Marshall Ward
The gray light of the waning moon, sifting through the boughs, was the true lumina for reverie.
The Mascot of Sweet Briar Gulch|Henry Wallace Phillips

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, adjective

Word 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 Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

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.