"tetrac-" meaning in Gaulois

{
  "categories": [
    {
      "kind": "other",
      "name": "Mots attestés en gaulois",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "Noms communs en gaulois",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "Wiktionnaire:Modèle étyl sans langue précisée",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "Gaulois",
      "orig": "gaulois",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "Étymologies en gaulois incluant une reconstruction",
      "parents": [],
      "source": "w"
    }
  ],
  "etymology_texts": [
    "Mot présent dans des noms propres Tetarus, Tettaro, etc.",
    "De l’Erreur modèle étyl : langue inconnue ou absente *teter(u̯o)-."
  ],
  "lang": "Gaulois",
  "lang_code": "gaulois",
  "pos": "noun",
  "pos_title": "Nom commun",
  "related": [
    {
      "word": "tetaro-"
    }
  ],
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "Mots en gaulois de sens incertain",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Oiseaux en gaulois",
          "parents": [],
          "source": "w"
        }
      ],
      "glosses": [
        "Coq de bruyère, faisan."
      ],
      "id": "fr-tetrac--gaulois-noun-tvP8CNmG",
      "raw_tags": [
        "Sens incertain"
      ],
      "topics": [
        "ornithology"
      ]
    }
  ],
  "word": "tetrac-"
}

{
  "categories": [
    "Mots attestés en gaulois",
    "Noms communs en gaulois",
    "Wiktionnaire:Modèle étyl sans langue précisée",
    "gaulois",
    "Étymologies en gaulois incluant une reconstruction"
  ],
  "etymology_texts": [
    "Mot présent dans des noms propres Tetarus, Tettaro, etc.",
    "De l’Erreur modèle étyl : langue inconnue ou absente *teter(u̯o)-."
  ],
  "lang": "Gaulois",
  "lang_code": "gaulois",
  "pos": "noun",
  "pos_title": "Nom commun",
  "related": [
    {
      "word": "tetaro-"
    }
  ],
  "senses": [
    {
      "categories": [
        "Mots en gaulois de sens incertain",
        "Oiseaux en gaulois"
      ],
      "glosses": [
        "Coq de bruyère, faisan."
      ],
      "raw_tags": [
        "Sens incertain"
      ],
      "topics": [
        "ornithology"
      ]
    }
  ],
  "word": "tetrac-"
}