"R6" meaning in French

{
  "forms": [
    {
      "form": "R6",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "f",
        "2": "#"
      },
      "expansion": "R6 f (plural R6)",
      "name": "fr-noun"
    }
  ],
  "lang": "French",
  "lang_code": "fr",
  "pos": "noun",
  "senses": [
    {
      "alt_of": [
        {
          "word": "Renault 6"
        }
      ],
      "categories": [
        {
          "kind": "other",
          "name": "French entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "French links with redundant alt parameters",
          "parents": [
            "Links with redundant alt parameters",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "French links with redundant wikilinks",
          "parents": [
            "Links with redundant wikilinks",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "fr",
          "name": "Automobiles",
          "orig": "fr:Automobiles",
          "parents": [
            "Automotive",
            "Vehicles",
            "Transport",
            "Machines",
            "All topics",
            "Technology",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "Short for Renault 6."
      ],
      "id": "en-R6-fr-noun-rWKkH8Vn",
      "links": [
        [
          "Renault 6",
          "w:Renault 6"
        ]
      ],
      "tags": [
        "abbreviation",
        "alt-of",
        "feminine"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "/ʁsis/"
    }
  ],
  "word": "R6"
}

{
  "forms": [
    {
      "form": "R6",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "f",
        "2": "#"
      },
      "expansion": "R6 f (plural R6)",
      "name": "fr-noun"
    }
  ],
  "lang": "French",
  "lang_code": "fr",
  "pos": "noun",
  "senses": [
    {
      "alt_of": [
        {
          "word": "Renault 6"
        }
      ],
      "categories": [
        "French 1-syllable words",
        "French countable nouns",
        "French entries with incorrect language header",
        "French feminine nouns",
        "French lemmas",
        "French links with redundant alt parameters",
        "French links with redundant wikilinks",
        "French nouns",
        "French short forms",
        "French terms spelled with numbers",
        "French terms with IPA pronunciation",
        "fr:Automobiles"
      ],
      "glosses": [
        "Short for Renault 6."
      ],
      "links": [
        [
          "Renault 6",
          "w:Renault 6"
        ]
      ],
      "tags": [
        "abbreviation",
        "alt-of",
        "feminine"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "/ʁsis/"
    }
  ],
  "word": "R6"
}