*SET-U

English word origin

Etymology of exo-

Etymology tree Ancient Greek ἐκ (ek) Ancient Greek ἔξω (éxō)der. English exo- From Ancient Greek ἔξω (éxō, “outer; external”).

1 source sectionExtended source reportWiktionary original ↗
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 ↗
prefix

outside; external · extrasolar; beyond the Solar System (our solar system)

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

Etymology tree Ancient Greek ἐκ (ek) Ancient Greek ἔξω (éxō)der. English exo- From Ancient Greek ἔξω (éxō, “outer; external”).

Relationships mentioned by the source

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

Inspect preserved source fields

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

{
  "templates": [
    {
      "name": "etymon",
      "args": {
        "1": "en",
        "2": ":der",
        "3": "grc:ἔξω",
        "tree": "1"
      },
      "expansion": "Etymology tree\nAncient Greek ἐκ (ek)\nAncient Greek ἔξω (éxō)der.\nEnglish exo-\n[Appendix:Glossary#derived_terms|Derived]] from\", \"terms\" : [ { \"children\" : [ { \"terms\" : [ { \"id\" : \"out\", \"children\" : [ ], \"status\" : \"missing\", \"lang_name\" : \"Ancient Greek\", \"term\" : \"ἐκ\", \"lang\" : \"grc\" } ], \"keyword_label\" : \"From\", \"keyword\" : \"from\" } ], \"lang_name\" : \"Ancient Greek\", \"term\" : \"ἔξω\", \"status\" : \"ok\", \"lang\" : \"grc\" } ], \"keyword\" : \"derived\" } ], \"lang_name\" : \"English\", \"term\" : \"exo-\", \"status\" : \"ok\", \"lang\" : \"en\" }\" data-lang=\"en\" data-title=\"exo-\">"
    },
    {
      "name": "der",
      "args": {
        "1": "en",
        "2": "grc",
        "3": "ἔξω",
        "4": "",
        "5": "outer; external"
      },
      "expansion": "Ancient Greek ἔξω (éxō, “outer; external”)"
    },
    {
      "name": "etymon",
      "args": {
        "1": "en",
        "2": ":der",
        "3": "grc:ἔξω",
        "tree": "1"
      },
      "expansion": "Etymology tree\nProto-Indo-European *h₁éǵʰ\nProto-Indo-European *-s\nProto-Indo-European *h₁eǵʰs\nProto-Hellenic *eks\nAncient Greek ἐκ (ek)\nAncient Greek ἔξω (éxō)der.\nEnglish exo-"
    }
  ],
  "links": [
    [
      "ἐκ",
      "ἐκ#Ancient_Greek:_out"
    ],
    [
      "ἔξω",
      "ἔξω#Ancient_Greek"
    ],
    [
      "ἔξω",
      "ἔξω#Ancient_Greek"
    ]
  ],
  "references": [],
  "descendants": [],
  "lexical": [
    {
      "pos": "prefix",
      "glosses": [
        "outside; external",
        "extrasolar; beyond the Solar System (our solar system)"
      ],
      "tags": [
        "morpheme"
      ],
      "recordId": "2229d5541ad3ee0410f817909cd1d609ad4704fdbf8bb111f3f8d728fcfd1433",
      "rawRecordSha256": "0d1d2dcaed22914d3bf4f3a47a29b73d0b821c94029b43177d5567e49bb980db",
      "sourceRecordOrdinal": 396220
    }
  ],
  "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 exo- →

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-ZXhvLQ