lumen
UK /ˈluːmən/ · US /ˈlumən/ noun
Forms lumens lumina
- noun (physics) In the International System of Units, the derived unit of luminous flux; the light that is emitted in a solid angle of one steradian from a source of one candela. Symbol: lm.
- noun (anatomy) The cavity or channel within a tube or tubular organ.
- noun (botany) The cavity bounded by a plant cell wall.
- noun (medicine) The bore of a tube such as a hollow needle or catheter.
Synonyms
Etymology
Borrowed from Latin lūmen (“light, an opening”). Use as a unit was first adopted by French physicist André Blondel in 1894.
Webster’s 1913
Sources: Wiktionary · WordNet 3.0 · Webster’s 1913 — from the Wiktionary entry “lumen”, CC BY-SA 4.0. Details