lumen

See also: lúmen

English

Etymology

Borrowed from Latin lumen (“light, an opening”). Use as a unit was first adopted by French physicist André Blondel in 1894.

Pronunciation

• (Received Pronunciation) IPA^(key): /ˈluːmən/
• (General American) enPR: lo͞oʹmən, IPA^(key): /ˈlumən/

• Audio (UK)

  (file)

• Rhymes: -uːmən
• Hyphenation: lu‧men

Noun

lumen (plural lumens or lumina)

1. (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.
2. (anatomy) The cavity or channel within a tube or tubular organ.
3. (botany) The cavity bounded by a plant cell wall.
4. (medicine) The bore of a tube such as a hollow needle or catheter.

Derived terms

• lumenal
• lumen second

Related terms

• candela
• luminal
• lux

Translations

SI-unit for luminous flux

• Arabic: لُومِن‎‎ m (lūmin)
• Armenian: լյումեն (hy) (lyumen)
• Chinese:

  Mandarin: 流明 (zh) (liúmíng)

• Czech: lumen (cs) m
• Finnish: luumen (fi)
• French: lumen (fr)
• German: Lumen (de) n

• Greek: λούμεν n (loúmen)
• Japanese: ルーメン (rūmen)
• Korean: 루멘 (rumen)
• Polish: lumen (pl) m
• Portuguese: lúmen (pt) m
• Russian: лю́мен (ru) m (ljúmen)
• Swedish: lumen (sv)
• Tagalog: lumen

anatomy: cavity within tubular organ

• Chinese:

  Mandarin: 內腔, 内腔 (nèiqiāng)

• Finnish: lumen (fi), ontelo (fi)
• Hebrew: נהור‎‎ m (n'hor)

• Japanese: 内腔 (ないくう, naikū)
• Korean: 내강 (naegang) (內腔)
• Portuguese: lúmen (pt) m

botany: cavity bounded by cell wall

• Finnish: lumen (fi), ontelo (fi)

• Russian: по́лость (ru) f (pólostʹ)

medicine: bore of a tube

• Finnish: lumen (fi)

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Czech

Noun

lumen m

1. lumen (unit of luminous flux)

Further reading

• lumen in Příruční slovník jazyka českého, 1935–1957
• lumen in Slovník spisovného jazyka českého, 1960–1971, 1989

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Finnish

Etymology 1

Alternative forms

• luumen

Pronunciation

• IPA^(key): /ˈluːmen/, [ˈluːme̞n]
• Rhymes: -uːmen
• Hyphenation: lu‧men

Noun

lumen

1. (physics, anatomy, botany, medicine) lumen

Declension

Inflection of lumen (Kotus type 6/paperi, no gradation)
nominative		lumen	lumenit
genitive		lumenin	lumenien lumeneiden lumeneitten
partitive		lumenia	lumeneita lumeneja
illative		lumeniin	lumeneihin
		singular	plural
nominative		lumen	lumenit
accusative	nom.	lumen	lumenit
	gen.	lumenin
genitive		lumenin	lumenien lumeneiden lumeneitten
partitive		lumenia	lumeneita lumeneja
inessive		lumenissa	lumeneissa
elative		lumenista	lumeneista
illative		lumeniin	lumeneihin
adessive		lumenilla	lumeneilla
ablative		lumenilta	lumeneilta
allative		lumenille	lumeneille
essive		lumenina	lumeneina
translative		lumeniksi	lumeneiksi
instructive		—	lumenein
abessive		lumenitta	lumeneitta
comitative		—	lumeneineen

Etymology 2

Pronunciation

• IPA^(key): /ˈlumen/, [ˈlume̞n]
• Hyphenation: lu‧men

Noun

lumen

1. Genitive singular form of lumi.

Anagrams

• lemun, melun

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Latin

Etymology

From Proto-Indo-European *léwksmn̥, derived from the root *lewk- (“bright”).
Equivalent to lūx +‎ -men.

Pronunciation

• (Classical) IPA^(key): /ˈluː.men/, [ˈɫuː.mẽ]
• (Ecclesiastical) IPA^(key): /ˈlu.men/, [ˈluː.men]

Noun

lūmen n (genitive lūminis); third declension

1. light
2. (poetic) the eyes
3. (poetic) daylight
4. (poetic) brightness
5. (poetic) the light of life
6. An opening through which light can penetrate such as an air-hole or a window.
7. The opening or orifice in a water-pipe or funnel

Inflection

Third declension neuter.

Case	Singular	Plural
nominative	lūmen	lūmina
genitive	lūminis	lūminum
dative	lūminī	lūminibus
accusative	lūmen	lūmina
ablative	lūmine	lūminibus
vocative	lūmen	lūmina

Derived terms

• lūmināre
• lūminātor
• lūminātus

• lūminō
• lūminōsus

Descendants

• Aromanian: lumi, lunjinã
• Asturian: llume
• Catalan: llum
• French: lumière
• Galician: lume
• Istriot: loûme
• Italian: lume

• Istro-Romanian: lume
• Occitan: lum
• Portuguese: lume
• Romanian: lume, lumină
• Russian: люмен (ljumen)
• Sicilian: lumi
• Spanish: lumbre

References

• lumen in Charlton T. Lewis and Charles Short (1879) A Latin Dictionary, Oxford: Clarendon Press
• lumen in Charlton T. Lewis (1891) An Elementary Latin Dictionary, New York: Harper & Brothers
• lumen in Charles du Fresne du Cange’s Glossarium Mediæ et Infimæ Latinitatis (augmented edition, 1883–1887)
• lumen in Gaffiot, Félix (1934) Dictionnaire Illustré Latin-Français, Hachette
• Carl Meissner; Henry William Auden (1894) Latin Phrase-Book‎^[1], London: Macmillan and Co.
  • to lose one's sight: oculos, lumina amittere
    
  • to deprive a person of his eyes: luminibus orbare aliquem
    
  • to obscure the mental vision: mentis quasi luminibus officere (vid. sect. XIII. 6) or animo caliginem offundere
    
  • shining lights in the literary world: clarissima litterarum lumina
    
  • flowers of rhetoric; embellishments of style: lumina, flores dicendi (De Or. 3. 25. 96)
    
  • to obstruct a person's view, shut out his light by building: luminibus alicuius obstruere, officere
    

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Polish

Noun

lumen m inan

1. lumen (SI-unit)

Declension

declension of lumen

	singular	plural
nominative	lumen	lumeny
genitive	lumena	lumenów
dative	lumenowi	lumenom
accusative	lumen	lumeny
instrumental	lumenem	lumenami
locative	lumenie	lumenach
vocative	lumenie	lumeny

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Spanish

Noun

lumen m (plural lúmenes)

1. lumen

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Swedish

Noun

lumen

1. lumen (singular and plural)