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Definition of “lumen” - English Dictionary

"lumen" in American English

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lumennoun [C]

/ˈlu·mən/
physics, earth science the standard unit for measuring the brightness of a light, equal to the amount of light hitting one square foot of surface one foot away from the light
(Definition of lumen from the Cambridge Academic Content Dictionary © Cambridge University Press)







"lumen" in British English

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lumennoun [C]

uk   /ˈluː.mən/ us   /ˈluː.mən/ specialized
  • lumen noun [C] (UNIT OF LIGHT)

abbreviation lm physics a unit for measuring the amount of light something produces: a light bulb rated at 750 lumens
  • lumen noun [C] (IN BODY)

plural lumina lumens medical the inside space of a tube-shaped organ in the body, for example a blood vessel or intestine: intestinal/vascular lumen
(Definition of lumen from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
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