*SET-U

English word origin

Etymology of theta

Borrowed from Ancient Greek θῆτα (thêta).

1 source sectionBrief source recordWiktionary 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 ↗
noun

The eighth letter of the Modern Greek alphabet, ninth in Old Greek: Θ, θ. · The measure of an angle. · Pitch angle; the angle between an aircraft's longitudinal axis and the horizontal plane. · The sensitivity of the value of a derivative with respect to time; the "time decay".

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

Borrowed from Ancient Greek θῆτα (thêta).

This page abbreviates 2 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": ":bor",
        "3": "grc:θῆτα",
        "text": "+",
        "tree": "1"
      },
      "expansion": "[Appendix:Glossary#loanword|Borrowed]] from\", \"terms\" : [ { \"children\" : [ ], \"lang_name\" : \"Ancient Greek\", \"term\" : \"θῆτα\", \"status\" : \"missing\", \"lang\" : \"grc\" } ], \"keyword\" : \"bor\" } ], \"lang_name\" : \"English\", \"term\" : \"theta\", \"status\" : \"ok\", \"lang\" : \"en\" }\" data-lang=\"en\" data-title=\"theta\">\nBorrowed from Ancient Greek θῆτα (thêta)."
    },
    {
      "name": "ety",
      "args": {
        "1": "en",
        "2": ":bor",
        "3": "grc:θῆτα",
        "text": "+",
        "tree": "1"
      },
      "expansion": "Borrowed from Ancient Greek θῆτα (thêta)."
    }
  ],
  "links": [
    [
      "θῆτα",
      "θῆτα#Ancient_Greek"
    ]
  ],
  "references": [],
  "descendants": [
    {
      "lang": "Malay",
      "lang_code": "ms",
      "word": "teta",
      "raw_tags": [
        "borrowed"
      ]
    }
  ],
  "lexical": [
    {
      "pos": "noun",
      "glosses": [
        "The eighth letter of the Modern Greek alphabet, ninth in Old Greek: Θ, θ.",
        "The measure of an angle.",
        "Pitch angle; the angle between an aircraft's longitudinal axis and the horizontal plane.",
        "The sensitivity of the value of a derivative with respect to time; the \"time decay\"."
      ],
      "tags": [
        "broadly"
      ],
      "recordId": "f395771e48f12889448918f10b1acb8fddccde4c8488bfa9f6bdb2d51e933d2d",
      "rawRecordSha256": "925d7131b378e64e22562e48d34c314cf19ba5b0cf37024db069a6f1bb4bbb32",
      "sourceRecordOrdinal": 123102
    }
  ],
  "omittedAuxiliaryFields": {
    "templates": 0,
    "links": 0,
    "references": 0,
    "descendants": 0,
    "lexicalRecords": 0,
    "lexicalSenses": 2,
    "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 theta →

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-dGhldGE