lumen
lu·men/ˈlumən/noun
lumen is spelled L-U-M-E-N: 5 letters and 2 syllables (lu·men). It appears 1.2 times per million words in written English, the 25,751st most frequent word form (wordfreq, 2021 data). As a noun, lumen means “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…” (English Wiktionary, September 2026). The plural of lumen is lumens or lumina.
How many letters and syllables are in lumen?
| Letters | 5: L-U-M-E-N |
|---|---|
| Syllables | 2: lu·men |
| In writing | 1.2 times per million words; the 25,751st most frequent word form |
| Wrong spellings searched | none measured in search |
| Rhymes with |
Sources: letters and syllables from the English Wiktionary's hyphenation or pronunciation; written frequency: wordfreq 3.1 (a 2021 snapshot of Wikipedia, subtitles, news, books, web text and social media); rhymes and same-letter words are computed by PlainSpell from its own word list.
How common is lumen?
Lumen appears 1.2 times per million words in written English, the 25,751st most frequent word form in the list.
Source: written frequency: wordfreq 3.1 (a 2021 snapshot of Wikipedia, subtitles, news, books, web text and social media).
How do you pronounce lumen?
- UK /ˈluːmən/
- US /ˈlumən/
Lumen has 2 syllables, split lu·men in writing.
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract). Recordings: En-uk-lumen.ogg, Wikimedia Commons (author and licence on each file's page).
What rhymes with lumen?
4 words on PlainSpell end in the same sounds as lumen from its last stressed vowel (/umən/):
Computed by PlainSpell from the pronunciations in the English Wiktionary (dump of September 2, 2026): a rhyme shares every sound from the last stressed vowel to the end; ordered by written frequency (wordfreq 3.1).
Forms of lumen
- lumens plural
- lumina plural
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).
What does lumen mean?
The meanings the English Wiktionary records, quoted as written there (source below).
noun
- 1
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
The cavity or channel within a tube or tubular organ.
- 3
The cavity bounded by a plant cell wall.
- 4
The bore of a tube such as a hollow needle or catheter.
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).
Lumen in Spanish, French, German and Portuguese
In the sense SI-unit for luminous flux:
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract). Translations are Wiktionary's, by sense; a linked word has its own PlainSpell page.
Where does lumen come from?
Borrowed from Latin lūmen (“light, an opening”). Use as a unit was first adopted by French physicist André Blondel in 1894.
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).