"zero" meaning in Conventions internationales

{
  "categories": [
    {
      "kind": "other",
      "name": "Alphabet d’épellation international",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "Noms scientifiques",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "Conventions internationales",
      "orig": "conventions internationales",
      "parents": [],
      "source": "w"
    }
  ],
  "lang": "Conventions internationales",
  "lang_code": "conv",
  "pos": "noun",
  "pos_title": "Nom scientifique",
  "senses": [
    {
      "glosses": [
        "(radiotéléphonie) Mot de code radiotéléphonique de l'OACI, OTAN et SIA pour le chiffre 0."
      ],
      "id": "fr-zero-conv-noun-jH6-piOC"
    }
  ],
  "sounds": [
    {
      "ipa": "\\ˈziˈro"
    },
    {
      "ipa": "ˈziro\\"
    }
  ],
  "word": "zero"
}

{
  "categories": [
    "Alphabet d’épellation international",
    "Noms scientifiques",
    "conventions internationales"
  ],
  "lang": "Conventions internationales",
  "lang_code": "conv",
  "pos": "noun",
  "pos_title": "Nom scientifique",
  "senses": [
    {
      "glosses": [
        "(radiotéléphonie) Mot de code radiotéléphonique de l'OACI, OTAN et SIA pour le chiffre 0."
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "\\ˈziˈro"
    },
    {
      "ipa": "ˈziro\\"
    }
  ],
  "word": "zero"
}