"Z0" 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"
    }
  ],
  "lang": "Conventions internationales",
  "lang_code": "conv",
  "pos": "symbol",
  "pos_title": "Symbole",
  "related": [
    {
      "sense": "femelle",
      "word": "ZW"
    },
    {
      "sense": "mâle",
      "word": "ZZ"
    }
  ],
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "Lexique en conventions internationales de la biologie",
          "parents": [],
          "source": "w"
        }
      ],
      "glosses": [
        "Femelle ayant un seul chromosome Z."
      ],
      "id": "fr-Z0-conv-symbol-fP--6z9S",
      "topics": [
        "biology"
      ]
    },
    {
      "categories": [
        {
          "kind": "other",
          "name": "Lexique en conventions internationales de la biologie",
          "parents": [],
          "source": "w"
        }
      ],
      "glosses": [
        "Système de détermination sexuelle où le mâle est ZZ et la femelle est Z0."
      ],
      "id": "fr-Z0-conv-symbol-KBkr9Hbn",
      "topics": [
        "biology"
      ]
    }
  ],
  "word": "Z0"
}

{
  "categories": [
    "Symboles en conventions internationales",
    "conventions internationales"
  ],
  "lang": "Conventions internationales",
  "lang_code": "conv",
  "pos": "symbol",
  "pos_title": "Symbole",
  "related": [
    {
      "sense": "femelle",
      "word": "ZW"
    },
    {
      "sense": "mâle",
      "word": "ZZ"
    }
  ],
  "senses": [
    {
      "categories": [
        "Lexique en conventions internationales de la biologie"
      ],
      "glosses": [
        "Femelle ayant un seul chromosome Z."
      ],
      "topics": [
        "biology"
      ]
    },
    {
      "categories": [
        "Lexique en conventions internationales de la biologie"
      ],
      "glosses": [
        "Système de détermination sexuelle où le mâle est ZZ et la femelle est Z0."
      ],
      "topics": [
        "biology"
      ]
    }
  ],
  "word": "Z0"
}