*SET-U

English word origin

Etymology of -o-

Adopted from Latin -o-, originating ultimately from Ancient Greek -ο- (-o-). In English, the connective is found from the Middle English period in direct borrowings from Latin. Direct formations of English terms with the

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 ↗
interfix

A linking vowel inserted interconsonantally between two morphemes, to ease pronunciation, without contributing to the meaning. It frequently joins words or combining forms of Ancient Greek or Classical Latin origin in the classical compounds of New Latin and international scientific vocabulary, but it can also be used to join modern terms and even abbreviations, either formally or informally.

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

Adopted from Latin -o-, originating ultimately from Ancient Greek -ο- (-o-). In English, the connective is found from the Middle English period in direct borrowings from Latin. Direct formations of English terms with the connective, always combining Greek or Latin roots, appear from the 16th or 17th century. From the 18th century, the suffix becomes productive in compounds where the second element is English. From about 1800, formations on all sorts of stems become common.

Relationships mentioned by the source

These are extracted mentions, not a timeline or a verified sequence of immediate parents.

  • Borrowed-form mention-o-la
  • Derivation mention-ο-grc
Inspect preserved source fields

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

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      "args": {
        "1": "combining forms"
      },
      "expansion": ""
    },
    {
      "name": "etymon",
      "args": {
        "1": "en",
        "2": ":bor",
        "3": "la:-o-<id:connective>",
        "id": "connective"
      },
      "expansion": "[Appendix:Glossary#loanword|Borrowed]] from\", \"terms\" : [ { \"id\" : \"connective\", \"children\" : [ { \"keyword_abbrev\" : \"der.\", \"keyword_label\" : \"Derived from\", \"terms\" : [ { \"id\" : \"connective\", \"children\" : [ ], \"status\" : \"missing\", \"lang_name\" : \"Ancient Greek\", \"term\" : \"-ο-\", \"lang\" : \"grc\" } ], \"keyword\" : \"derived\" } ], \"status\" : \"ok\", \"lang_name\" : \"Latin\", \"term\" : \"-o-\", \"lang\" : \"la\" } ], \"keyword\" : \"bor\" } ], \"status\" : \"ok\", \"lang_name\" : \"English\", \"term\" : \"-o-\", \"lang\" : \"en\" }\" data-id=\"connective\" data-lang=\"en\" data-title=\"-o-\" id=\"English:_connective\">"
    },
    {
      "name": "bor",
      "args": {
        "1": "en",
        "2": "la",
        "3": "-o-"
      },
      "expansion": "Latin -o-"
    },
    {
      "name": "der",
      "args": {
        "1": "en",
        "2": "grc",
        "3": "-ο-"
      },
      "expansion": "Ancient Greek -ο- (-o-)"
    },
    {
      "name": "etymon",
      "args": {
        "1": "en",
        "2": ":bor",
        "3": "la:-o-<id:connective>",
        "id": "connective"
      },
      "expansion": ""
    }
  ],
  "links": [
    [
      "-o-",
      "-o-#Latin"
    ],
    [
      "-ο-",
      "-ο-#Ancient_Greek"
    ]
  ],
  "references": [],
  "descendants": [],
  "lexical": [
    {
      "pos": "interfix",
      "glosses": [
        "A linking vowel inserted interconsonantally between two morphemes, to ease pronunciation, without contributing to the meaning. It frequently joins words or combining forms of Ancient Greek or Classical Latin origin in the classical compounds of New Latin and international scientific vocabulary, but it can also be used to join modern terms and even abbreviations, either formally or informally."
      ],
      "tags": [
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  }
}

Source etymology 2

Original entry ↗
interfix

a monoclonal antibody derived from a murine source

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

Designated in the USAN guidelines for non-proprietary names of monoclonal antibodies.

Inspect preserved source fields

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

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  "templates": [],
  "links": [],
  "references": [],
  "descendants": [],
  "lexical": [
    {
      "pos": "interfix",
      "glosses": [
        "a monoclonal antibody derived from a murine source"
      ],
      "tags": [
        "morpheme"
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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.

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 -o- →

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-LW8t