"Breta" meaning in Middle Irish

{
  "etymology_templates": [
    {
      "args": {
        "1": "mga",
        "2": "Britain",
        "gloss": "Britons"
      },
      "expansion": "Back-formation of Britain (“Britons”)",
      "name": "back-formation"
    }
  ],
  "etymology_text": "Back-formation of Britain (“Britons”).",
  "forms": [
    {
      "form": "no-table-tags",
      "source": "mutation",
      "tags": [
        "table-tags"
      ]
    },
    {
      "form": "Breta",
      "source": "mutation",
      "tags": [
        "error-unrecognized-form"
      ]
    },
    {
      "form": "mBreta",
      "source": "mutation",
      "tags": [
        "error-unrecognized-form"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "mga",
        "2": "proper noun",
        "g": "f"
      },
      "expansion": "Breta f",
      "name": "head"
    }
  ],
  "lang": "Middle Irish",
  "lang_code": "mga",
  "pos": "name",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "Middle Irish back-formations",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Middle Irish entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "place",
          "langcode": "mga",
          "name": "British Isles",
          "orig": "mga:British Isles",
          "parents": [
            "Europe",
            "Islands",
            "Earth",
            "Eurasia",
            "Places",
            "Nature",
            "Names",
            "All topics",
            "Proper nouns",
            "Terms by semantic function",
            "Fundamental",
            "Nouns",
            "Lemmas"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "Britain"
      ],
      "id": "en-Breta-mga-name-DrBFMB7z",
      "links": [
        [
          "Britain",
          "Britain"
        ]
      ],
      "tags": [
        "feminine"
      ]
    }
  ],
  "word": "Breta"
}

{
  "etymology_templates": [
    {
      "args": {
        "1": "mga",
        "2": "Britain",
        "gloss": "Britons"
      },
      "expansion": "Back-formation of Britain (“Britons”)",
      "name": "back-formation"
    }
  ],
  "etymology_text": "Back-formation of Britain (“Britons”).",
  "forms": [
    {
      "form": "no-table-tags",
      "source": "mutation",
      "tags": [
        "table-tags"
      ]
    },
    {
      "form": "Breta",
      "source": "mutation",
      "tags": [
        "error-unrecognized-form"
      ]
    },
    {
      "form": "mBreta",
      "source": "mutation",
      "tags": [
        "error-unrecognized-form"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "mga",
        "2": "proper noun",
        "g": "f"
      },
      "expansion": "Breta f",
      "name": "head"
    }
  ],
  "lang": "Middle Irish",
  "lang_code": "mga",
  "pos": "name",
  "senses": [
    {
      "categories": [
        "Middle Irish back-formations",
        "Middle Irish entries with incorrect language header",
        "Middle Irish feminine nouns",
        "Middle Irish lemmas",
        "Middle Irish proper nouns",
        "Pages with 1 entry",
        "Pages with entries",
        "mga:British Isles"
      ],
      "glosses": [
        "Britain"
      ],
      "links": [
        [
          "Britain",
          "Britain"
        ]
      ],
      "tags": [
        "feminine"
      ]
    }
  ],
  "word": "Breta"
}

{
  "called_from": "inflection/865",
  "msg": "inflection table: IF WITHOUT ELSE EVALS False: Breta/Middle Irish 'radical' base_tags=set()",
  "path": [
    "Breta"
  ],
  "section": "Middle Irish",
  "subsection": "proper noun",
  "title": "Breta",
  "trace": ""
}

{
  "called_from": "inflection/735",
  "msg": "inflection table: unrecognized header: 'lenition'",
  "path": [
    "Breta"
  ],
  "section": "Middle Irish",
  "subsection": "proper noun",
  "title": "Breta",
  "trace": ""
}

{
  "called_from": "inflection/735",
  "msg": "inflection table: unrecognized header: 'nasalization'",
  "path": [
    "Breta"
  ],
  "section": "Middle Irish",
  "subsection": "proper noun",
  "title": "Breta",
  "trace": ""
}