"NA" meaning in Conventions internationales

{
  "categories": [
    {
      "kind": "other",
      "name": "Symboles en conventions internationales",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "Conventions internationales",
      "orig": "conventions internationales",
      "parents": [],
      "source": "w"
    }
  ],
  "etymology_texts": [
    "(Automobile) (1956) Sigle du néerlandais Nederlandse Antillen."
  ],
  "lang": "Conventions internationales",
  "lang_code": "conv",
  "pos": "symbol",
  "pos_title": "Symbole 1",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "Lexique en conventions internationales de l’automobile",
          "parents": [],
          "source": "w"
        }
      ],
      "glosses": [
        "Signe distinctif en trafic international des véhicules automobiles immatriculés aux Antilles néerlandaises, prescrit dans le cadre de la Convention sur la circulation routière de Genève de 1949 et de la Convention sur la signalisation routière de Vienne de 1968."
      ],
      "id": "fr-NA-conv-symbol-W5ahwPSd",
      "topics": [
        "automobile"
      ]
    }
  ],
  "tags": [
    "invariable"
  ],
  "word": "NA"
}

{
  "categories": [
    {
      "kind": "other",
      "name": "Symboles en conventions internationales",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "Conventions internationales",
      "orig": "conventions internationales",
      "parents": [],
      "source": "w"
    }
  ],
  "etymology_texts": [
    "(Automobile) (1956) Sigle du néerlandais Nederlandse Antillen."
  ],
  "lang": "Conventions internationales",
  "lang_code": "conv",
  "pos": "symbol",
  "pos_title": "Symbole 2",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "Lexique en conventions internationales de la géographie",
          "parents": [],
          "source": "w"
        }
      ],
      "glosses": [
        "Code ISO 3166-1 (alpha-2) de la Namibie."
      ],
      "id": "fr-NA-conv-symbol-jqryhx6T",
      "topics": [
        "geography"
      ]
    }
  ],
  "tags": [
    "invariable"
  ],
  "word": "NA"
}

{
  "categories": [
    {
      "kind": "other",
      "name": "Symboles en conventions internationales",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "Conventions internationales",
      "orig": "conventions internationales",
      "parents": [],
      "source": "w"
    }
  ],
  "etymology_texts": [
    "(Automobile) (1956) Sigle du néerlandais Nederlandse Antillen."
  ],
  "lang": "Conventions internationales",
  "lang_code": "conv",
  "pos": "symbol",
  "pos_title": "Symbole 3",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "Lexique en conventions internationales de la physique",
          "parents": [],
          "source": "w"
        }
      ],
      "examples": [
        {
          "text": "la constante d’Avogadro, N_A, est égale à 6,022 140 76 × 1023 mol−1 — (Le système internationale des unités 9ᵉ édition, p.13, 2019 → lire en ligne)"
        }
      ],
      "glosses": [
        "Symbole du nombre d'Avogadro."
      ],
      "id": "fr-NA-conv-symbol-tYkxP7WM",
      "tags": [
        "physical"
      ]
    }
  ],
  "tags": [
    "invariable"
  ],
  "word": "NA"
}

{
  "categories": [
    "Symboles en conventions internationales",
    "conventions internationales"
  ],
  "etymology_texts": [
    "(Automobile) (1956) Sigle du néerlandais Nederlandse Antillen."
  ],
  "lang": "Conventions internationales",
  "lang_code": "conv",
  "pos": "symbol",
  "pos_title": "Symbole 1",
  "senses": [
    {
      "categories": [
        "Lexique en conventions internationales de l’automobile"
      ],
      "glosses": [
        "Signe distinctif en trafic international des véhicules automobiles immatriculés aux Antilles néerlandaises, prescrit dans le cadre de la Convention sur la circulation routière de Genève de 1949 et de la Convention sur la signalisation routière de Vienne de 1968."
      ],
      "topics": [
        "automobile"
      ]
    }
  ],
  "tags": [
    "invariable"
  ],
  "word": "NA"
}

{
  "categories": [
    "Symboles en conventions internationales",
    "conventions internationales"
  ],
  "etymology_texts": [
    "(Automobile) (1956) Sigle du néerlandais Nederlandse Antillen."
  ],
  "lang": "Conventions internationales",
  "lang_code": "conv",
  "pos": "symbol",
  "pos_title": "Symbole 2",
  "senses": [
    {
      "categories": [
        "Lexique en conventions internationales de la géographie"
      ],
      "glosses": [
        "Code ISO 3166-1 (alpha-2) de la Namibie."
      ],
      "topics": [
        "geography"
      ]
    }
  ],
  "tags": [
    "invariable"
  ],
  "word": "NA"
}

{
  "categories": [
    "Symboles en conventions internationales",
    "conventions internationales"
  ],
  "etymology_texts": [
    "(Automobile) (1956) Sigle du néerlandais Nederlandse Antillen."
  ],
  "lang": "Conventions internationales",
  "lang_code": "conv",
  "pos": "symbol",
  "pos_title": "Symbole 3",
  "senses": [
    {
      "categories": [
        "Lexique en conventions internationales de la physique"
      ],
      "examples": [
        {
          "text": "la constante d’Avogadro, N_A, est égale à 6,022 140 76 × 1023 mol−1 — (Le système internationale des unités 9ᵉ édition, p.13, 2019 → lire en ligne)"
        }
      ],
      "glosses": [
        "Symbole du nombre d'Avogadro."
      ],
      "tags": [
        "physical"
      ]
    }
  ],
  "tags": [
    "invariable"
  ],
  "word": "NA"
}