lumen
UK: ˈluːmɛn | US: ˈluːmən
n. the SI unit of luminous flux, equal to the amount of light emitted per second in a unit solid angle by a uniform point source of one candela.
n. (Anatomy/Biology) the central cavity of a tubular structure, such as a blood vessel or intestine.
lumen = lum<light> + en<noun suffix>
- lum<light>: From Latin lumen ("light, opening"), derived from lucēre ("to shine").
- en: A Latin noun-forming suffix indicating a state or result.
Etymology Origin:
The word lumen traces back to Latin, where it originally meant "light" or "an opening through which light passes." This dual meaning reflects its modern usage in both physics (as a unit of light measurement) and anatomy (as the hollow space within tubular structures, metaphorically akin to a "light passage"). The root lum- is shared with other light-related words like illuminate and luminous, emphasizing brightness and clarity.
The bulb emits a brightness of 800 lumens, ideal for reading.
The surgeon carefully examined the lumen of the artery for blockages.
Plants absorb light energy measured in lumens for photosynthesis.
A narrowed intestinal lumen can cause digestive issues.
Modern LED lights achieve high lumens with low energy consumption.