"variabile libera" meaning in Italien

{
  "categories": [
    {
      "kind": "other",
      "name": "Locutions nominales en italien",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "Italien",
      "orig": "italien",
      "parents": [],
      "source": "w"
    }
  ],
  "forms": [
    {
      "form": "variabili libere",
      "tags": [
        "plural"
      ]
    }
  ],
  "lang": "Italien",
  "lang_code": "it",
  "pos": "noun",
  "pos_title": "Locution nominale",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "Lexique en italien des mathématiques",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Wiktionnaire:Exemples manquants en italien",
          "parents": [],
          "source": "w"
        }
      ],
      "glosses": [
        "Variable libre, variable non utilisée par un mutificateur."
      ],
      "id": "fr-variabile_libera-it-noun-Mu~kE2-f",
      "topics": [
        "mathematics"
      ]
    }
  ],
  "tags": [
    "feminine"
  ],
  "word": "variabile libera"
}

{
  "categories": [
    "Locutions nominales en italien",
    "italien"
  ],
  "forms": [
    {
      "form": "variabili libere",
      "tags": [
        "plural"
      ]
    }
  ],
  "lang": "Italien",
  "lang_code": "it",
  "pos": "noun",
  "pos_title": "Locution nominale",
  "senses": [
    {
      "categories": [
        "Lexique en italien des mathématiques",
        "Wiktionnaire:Exemples manquants en italien"
      ],
      "glosses": [
        "Variable libre, variable non utilisée par un mutificateur."
      ],
      "topics": [
        "mathematics"
      ]
    }
  ],
  "tags": [
    "feminine"
  ],
  "word": "variabile libera"
}