*SET-U

English word origin

Etymology of co-

Etymology tree Proto-Indo-European *ḱe? Proto-Indo-European *ḱóm Proto-Italic *kom Proto-Italic *kom- Latin con- Latin co-lbor. English co- Learned borrowing from Latin co-, from con-, from Proto-Italic *kom-, from *kom,

2 source sectionsExtended source reportWiktionary original ↗
In this entry · 2 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.

Source etymology 1

Original entry ↗
prefix

Jointly: the root verb is done in coordination between multiple actors or entities · Along with: the root verb is done along with or in addition to others. · Mutually: the root is done in a way that is reciprocal and bidirectional. · Simultaneously, done or able to do at the same time.

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

Etymology tree Proto-Indo-European *ḱe? Proto-Indo-European *ḱóm Proto-Italic *kom Proto-Italic *kom- Latin con- Latin co-lbor. English co- Learned borrowing from Latin co-, from con-, from Proto-Italic *kom-, from *kom, from Proto-Indo-European *ḱóm, possibly from *ḱe.

This page abbreviates 16 auxiliary source items. The etymology narrative is not shortened. Omission counts are available in the audit fields below; consult the original for complete auxiliary material.

Inspect preserved source fields

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

{
  "templates": [
    {
      "name": "ety",
      "args": {
        "1": "en",
        "2": ":lbor",
        "3": "la:co-",
        "tree": "1",
        "text": "++"
      },
      "expansion": "Etymology tree\nProto-Indo-European *ḱe?\nProto-Indo-European *ḱóm\nProto-Italic *kom\nProto-Italic *kom-\nLatin con-\nLatin co-lbor.\nEnglish co-\n[Appendix:Glossary#learned_borrowing|Learned borrowing]] from\", \"terms\" : [ { \"children\" : [ { \"terms\" : [ { \"id\" : \"bringing together\", \"children\" : [ { \"terms\" : [ { \"id\" : \"with\", \"children\" : [ { \"terms\" : [ { \"id\" : \"with\", \"children\" : [ { \"terms\" : [ { \"id\" : \"beside\", \"children\" : [ { \"terms\" : [ { \"is_uncertain\" : true, \"id\" : \"here\", \"children\" : [ ], \"status\" : \"ok\", \"lang_name\" : \"Proto-Indo-European\", \"term\" : \"*ḱe\", \"lang\" : \"ine-pro\" } ], \"keyword_label\" : \"From\", \"keyword\" : \"from\" } ], \"status\" : \"ok\", \"lang_name\" : \"Proto-Indo-European\", \"term\" : \"*ḱóm\", \"lang\" : \"ine-pro\" } ], \"keyword_label\" : \"Inherited from\", \"keyword\" : \"inherited\" } ], \"status\" : \"ok\", \"lang_name\" : \"Proto-Italic\", \"term\" : \"*kom\", \"lang\" : \"itc-pro\" } ], \"keyword_label\" : \"From\", \"keyword\" : \"from\" } ], \"status\" : \"ok\", \"lang_name\" : \"Proto-Italic\", \"term\" : \"*kom-\", \"lang\" : \"itc-pro\" } ], \"keyword_label\" : \"Inherited from\", \"keyword\" : \"inherited\" } ], \"status\" : \"ok\", \"lang_name\" : \"Latin\", \"term\" : \"con-\", \"lang\" : \"la\" } ], \"keyword_label\" : \"From\", \"keyword\" : \"from\" } ], \"lang_name\" : \"Latin\", \"term\" : \"co-\", \"status\" : \"ok\", \"lang\" : \"la\" } ], \"keyword\" : \"lbor\" } ], \"lang_name\" : \"English\", \"term\" : \"co-\", \"status\" : \"ok\", \"lang\" : \"en\" }\" data-lang=\"en\" data-title=\"co-\">\nLearned borrowing from Latin co-, from con-, from Proto-Italic *kom-, from *kom, from Proto-Indo-European *ḱóm, possibly from *ḱe."
    },
    {
      "name": "ety",
      "args": {
        "1": "en",
        "2": ":lbor",
        "3": "la:co-",
        "tree": "1",
        "text": "++"
      },
      "expansion": "Etymology tree\nProto-Indo-European *ḱe?\nProto-Indo-European *ḱóm\nProto-Italic *kom\nProto-Italic *kom-\nLatin con-\nLatin co-lbor.\nEnglish co-\nLearned borrowing from Latin co-, from con-, from Proto-Italic *kom-, from *kom, from Proto-Indo-European *ḱóm, possibly from *ḱe."
    }
  ],
  "links": [
    [
      "*ḱe",
      "Reconstruction:Proto-Indo-European/ḱe#Proto-Indo-European:_here"
    ],
    [
      "*ḱóm",
      "Reconstruction:Proto-Indo-European/ḱóm#Proto-Indo-European:_beside"
    ],
    [
      "*kom",
      "Reconstruction:Proto-Italic/kom#Proto-Italic:_with"
    ],
    [
      "*kom-",
      "Reconstruction:Proto-Italic/kom-#Proto-Italic:_with"
    ],
    [
      "con-",
      "con-#Latin:_bringing_together"
    ],
    [
      "co-",
      "co-#Latin"
    ],
    [
      "co-",
      "co-#Latin"
    ],
    [
      "con-",
      "con-#Latin:_bringing_together"
    ],
    [
      "*kom-",
      "Reconstruction:Proto-Italic/kom-#Proto-Italic:_with"
    ],
    [
      "*kom",
      "Reconstruction:Proto-Italic/kom#Proto-Italic:_with"
    ],
    [
      "*ḱóm",
      "Reconstruction:Proto-Indo-European/ḱóm#Proto-Indo-European:_beside"
    ],
    [
      "*ḱe",
      "Reconstruction:Proto-Indo-European/ḱe#Proto-Indo-European:_here"
    ]
  ],
  "references": [],
  "descendants": [],
  "lexical": [
    {
      "pos": "prefix",
      "glosses": [
        "Jointly: the root verb is done in coordination between multiple actors or entities",
        "Along with: the root verb is done along with or in addition to others.",
        "Mutually: the root is done in a way that is reciprocal and bidirectional.",
        "Simultaneously, done or able to do at the same time."
      ],
      "tags": [
        "morpheme"
      ],
      "recordId": "cf856344d8df07ee7a56e3077bc0b5acd2917bb68b18365fa92b4ec592ff63de",
      "rawRecordSha256": "fc9438a85902192f2997a17781464d097aefb48855951cdce9628ea83804ff1b",
      "sourceRecordOrdinal": 400916
    }
  ],
  "omittedAuxiliaryFields": {
    "templates": 0,
    "links": 0,
    "references": 0,
    "descendants": 0,
    "lexicalRecords": 0,
    "lexicalSenses": 16,
    "glosses": 0
  }
}

Source etymology 2

Original entry ↗
prefix

Initialism of class of; prefixed to a full or abbreviated year number.

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

Initialism of class of.

Inspect preserved source fields

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

{
  "templates": [
    {
      "name": "init",
      "args": {
        "1": "en",
        "2": "class of"
      },
      "expansion": "Initialism of class of"
    }
  ],
  "links": [
    [
      "class",
      "class#English"
    ],
    [
      "of",
      "of#English"
    ]
  ],
  "references": [],
  "descendants": [],
  "lexical": [
    {
      "pos": "prefix",
      "glosses": [
        "Initialism of class of; prefixed to a full or abbreviated year number."
      ],
      "tags": [
        "abbreviation",
        "alt-of",
        "informal",
        "initialism",
        "morpheme"
      ],
      "recordId": "1e1c5006af6a3995e38652994aa5a2fffa40e6ceebee567526d951a2ef219f12",
      "rawRecordSha256": "225e089f62a12742316b67446c5b8775aa916e0e82173be51c582666770394c1",
      "sourceRecordOrdinal": 400917
    }
  ],
  "omittedAuxiliaryFields": {
    "templates": 0,
    "links": 0,
    "references": 0,
    "descendants": 0,
    "lexicalRecords": 0,
    "lexicalSenses": 0,
    "glosses": 0
  }
}

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.

An older meaning does not determine what a word must mean today. Follow the sources, preserve disagreements, and keep ancestry separate from interpretation.

Contribute located evidence for co- →

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
5ff2c072f8099f2d2ce484bd6957bf179f046d2ad37bc36555edf8bb84cb5291
Import run
73216b9a9b78ed3830994bf853103716f5a4dc57099e371e9f8fdc468facca26
Permanent entry ID
w-Y28t