noun, plural luces [loo-seez] . Optics.
a unit of illumination, equivalent to 0.0929 foot-candle and equal to the illumination produced by luminous flux of one lumen falling perpendicularly on a surface one meter square. Symbol: lx
Also called meter-candle.

1885–90; < Latin lūx light1 Unabridged


fiat lux

[fee-aht looks; English fee-aht luhks, fahy-uht] .
let there be light. Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
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World English Dictionary
lux1 (lʌks)
n , pl lux
lx the derived SI unit of illumination equal to a luminous flux of 1 lumen per square metre. 1 lux is equivalent to 0.0929 foot-candle
[C19: from Latin: light]

lux2 (lʌks)
informal (NZ) to clean with a vacuum cleaner
[C20: from Electrolux, a vacuum-cleaner manufacturer]

abbreviation for

Collins English Dictionary - Complete & Unabridged 10th Edition
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Word Origin & History

unit of illumination, 1889, from L. lux "light."
Online Etymology Dictionary, © 2010 Douglas Harper
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American Heritage
Medical Dictionary

lux (lŭks)
n. pl. lux·es or lu·ces (lōō'sēz)
Abbr. lx
The International System unit of illumination, equal to one lumen per square meter. Also called candle-meter, meter-candle.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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American Heritage
Science Dictionary
lux   (lŭks)  Pronunciation Key 
Plural luxes or luces (l'sēz)
A SI derived unit of illuminance in photometry, equal to one lumen per square meter.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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American Heritage
Abbreviations & Acronyms
The American Heritage® Abbreviations Dictionary, Third Edition
Copyright © 2005 by Houghton Mifflin Company.
Published by Houghton Mifflin Company. All rights reserved.
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Encyclopedia Britannica


unit of illumination (see luminous intensity) in the International System of Units (SI). One lux (Latin for "light") is the amount of illumination provided when one lumen is evenly distributed over an area of one square metre. This is also equivalent to the illumination that would exist on a surface all points of which are one metre from a point source of one international candle (candela). One lux is equal to 0.0929 foot-candle.

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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
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