*SET-U

English word origin

Etymology of lumen

Etymology tree Proto-Indo-European *lewk- Proto-Indo-European *-s- Proto-Indo-European *-mn̥ Proto-Indo-European *léwksmn̥ Proto-Italic *louksmən Latin lūmenbor. English lumen Borrowed from Latin lūmen (“light, an openin

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In this entry · 1 source sections

The source etymologies

Wiktionary via Kaikki / Wiktextract

The source reports below are imported and unreviewed by *SET-U. Separate numbered origins and differing source variants are preserved; agreement within this extraction is not independent corroboration.

Unnumbered source etymology

Original entry ↗
noun

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. · The cavity or channel within a tube or tubular organ. · The cavity bounded by a plant cell wall. · The bore of a tube such as a hollow needle or catheter.

Selected source glosses provide context, not a complete modern definition inventory

Etymology tree Proto-Indo-European *lewk- Proto-Indo-European *-s- Proto-Indo-European *-mn̥ Proto-Indo-European *léwksmn̥ Proto-Italic *louksmən Latin lūmenbor. English lumen Borrowed from Latin lūmen (“light, an opening”). Use as a unit was first adopted by French physicist André Blondel in 1894.

Inspect preserved source fields

Raw extraction fields are retained for auditing. Their order does not establish ancestry.

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    {
      "name": "ety",
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        "1": "en",
        "2": ":bor",
        "3": "la:lūmen<t:light, an opening>",
        "text": "1",
        "tree": "1"
      },
      "expansion": "Etymology tree\nProto-Indo-European *lewk-\nProto-Indo-European *-s-\nProto-Indo-European *-mn̥\nProto-Indo-European *léwksmn̥\nProto-Italic *louksmən\nLatin lūmenbor.\nEnglish lumen\n[Appendix:Glossary#loanword|Borrowed]] from\", \"terms\" : [ { \"gloss\" : \"light, an opening\", \"children\" : [ { \"terms\" : [ { \"children\" : [ { \"terms\" : [ { \"alt\" : \"*léwksmn̥\", \"lang_name\" : \"Proto-Indo-European\", \"status\" : \"inline\", \"children\" : [ { \"terms\" : [ { \"children\" : [ ], \"lang_name\" : \"Proto-Indo-European\", \"term\" : \"*lewk-\", \"status\" : \"ok\", \"lang\" : \"ine-pro\" }, { \"alt\" : \"*-s-\", \"lang_name\" : \"Proto-Indo-European\", \"status\" : \"ok\", \"children\" : [ ], \"lang\" : \"ine-pro\" }, { \"children\" : [ ], \"lang_name\" : \"Proto-Indo-European\", \"term\" : \"*-mn̥\", \"status\" : \"ok\", \"lang\" : \"ine-pro\" } ], \"keyword_label\" : \"From\", \"is_group\" : true, \"keyword\" : \"affix\" } ], \"lang\" : \"ine-pro\" } ], \"keyword_label\" : \"Inherited from\", \"keyword\" : \"inherited\" } ], \"lang_name\" : \"Proto-Italic\", \"term\" : \"*louksmən\", \"status\" : \"inline\", \"lang\" : \"itc-pro\" } ], \"keyword_label\" : \"Inherited from\", \"keyword\" : \"inherited\" } ], \"lang_name\" : \"Latin\", \"term\" : \"lūmen\", \"status\" : \"ok\", \"lang\" : \"la\" } ], \"keyword\" : \"bor\" } ], \"lang_name\" : \"English\", \"term\" : \"lumen\", \"status\" : \"ok\", \"lang\" : \"en\" }\" data-lang=\"en\" data-title=\"lumen\">\nBorrowed from Latin lūmen (“light, an opening”)."
    },
    {
      "name": "ety",
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        "1": "en",
        "2": ":bor",
        "3": "la:lūmen<t:light, an opening>",
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      },
      "expansion": "Etymology tree\nProto-Indo-European *lewk-\nProto-Indo-European *-s-\nProto-Indo-European *-mn̥\nProto-Indo-European *léwksmn̥\nProto-Italic *louksmən\nLatin lūmenbor.\nEnglish lumen\nBorrowed from Latin lūmen (“light, an opening”)."
    }
  ],
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      "*lewk-",
      "Reconstruction:Proto-Indo-European/lewk-"
    ],
    [
      "*-mn̥",
      "Reconstruction:Proto-Indo-European/-mn̥"
    ],
    [
      "*louksmən",
      "Reconstruction:Proto-Italic/louksmən"
    ],
    [
      "lūmen",
      "lumen#Latin"
    ],
    [
      "lūmen",
      "lumen#Latin"
    ]
  ],
  "references": [],
  "descendants": [],
  "lexical": [
    {
      "pos": "noun",
      "glosses": [
        "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.",
        "The cavity or channel within a tube or tubular organ.",
        "The cavity bounded by a plant cell wall.",
        "The bore of a tube such as a hollow needle or catheter."
      ],
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Where this record stops

This page does not supply an independently verified sound-change sequence, first-use manuscript or complete family tree unless a cited analysis explicitly establishes one. Missing detail here is a limit of this record—not a claim that humanity knows nothing more.

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Contribute located evidence for lumen →

Source and snapshot

Imported from Wiktionary contributors; extracted by Tatu Ylonen / Wiktextract / Kaikki.org. Selected fields are reformatted and grouped; wording, source identity and etymology sections are retained. CC-BY-SA-4.0 applies to the imported source material.

Dump: 2026-10-01 · Extracted: 2026-10-30. These are snapshot dates, not the word’s first attestation or the page’s revision date.

Source entry and bibliography ↗Wiktionary revision history ↗Acquisition and rights ledger
Machine-source provenance
Source SHA-256
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Import run
73216b9a9b78ed3830994bf853103716f5a4dc57099e371e9f8fdc468facca26
Permanent entry ID
w-bHVtZW4