"langue franche" meaning in Français

{
  "categories": [
    {
      "kind": "other",
      "name": "Locutions nominales en français",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "Français",
      "orig": "français",
      "parents": [],
      "source": "w"
    }
  ],
  "forms": [
    {
      "form": "langues franches",
      "tags": [
        "plural"
      ]
    }
  ],
  "lang": "Français",
  "lang_code": "fr",
  "pos": "noun",
  "pos_title": "Locution nominale",
  "related": [
    {
      "word": "langue véhiculaire"
    },
    {
      "word": "pidgin"
    },
    {
      "word": "sabir"
    },
    {
      "word": "esperanto"
    }
  ],
  "senses": [
    {
      "glosses": [
        "Vieux francique, langue des Francs."
      ],
      "id": "fr-langue_franche-fr-noun-ts7CY7Rt"
    },
    {
      "glosses": [
        "Ancien jargon maritime méditerranéen."
      ],
      "id": "fr-langue_franche-fr-noun-Uy8cQYIe"
    },
    {
      "glosses": [
        "Langue véhiculaire, langue commune permettant à des groupes de personnes ayant des langues maternelles différentes de se comprendre."
      ],
      "id": "fr-langue_franche-fr-noun-ZIv9DoOc"
    }
  ],
  "sounds": [
    {
      "ipa": "\\lɑ̃ɡ fʁɑ̃ʃ\\"
    }
  ],
  "synonyms": [
    {
      "word": "lingua franca"
    },
    {
      "word": "langue franque"
    }
  ],
  "tags": [
    "feminine"
  ],
  "word": "langue franche"
}

{
  "categories": [
    "Locutions nominales en français",
    "français"
  ],
  "forms": [
    {
      "form": "langues franches",
      "tags": [
        "plural"
      ]
    }
  ],
  "lang": "Français",
  "lang_code": "fr",
  "pos": "noun",
  "pos_title": "Locution nominale",
  "related": [
    {
      "word": "langue véhiculaire"
    },
    {
      "word": "pidgin"
    },
    {
      "word": "sabir"
    },
    {
      "word": "esperanto"
    }
  ],
  "senses": [
    {
      "glosses": [
        "Vieux francique, langue des Francs."
      ]
    },
    {
      "glosses": [
        "Ancien jargon maritime méditerranéen."
      ]
    },
    {
      "glosses": [
        "Langue véhiculaire, langue commune permettant à des groupes de personnes ayant des langues maternelles différentes de se comprendre."
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "\\lɑ̃ɡ fʁɑ̃ʃ\\"
    }
  ],
  "synonyms": [
    {
      "word": "lingua franca"
    },
    {
      "word": "langue franque"
    }
  ],
  "tags": [
    "feminine"
  ],
  "word": "langue franche"
}