"car mileage" meaning in English

{
  "head_templates": [
    {
      "args": {
        "1": "?"
      },
      "expansion": "car mileage",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "_dis": "84 16",
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
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          "source": "w+disamb"
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      ],
      "glosses": [
        "car miles collectively"
      ],
      "id": "en-car_mileage-en-noun-XCiXQ~zc",
      "links": [
        [
          "car mile",
          "car mile"
        ]
      ],
      "raw_glosses": [
        "(railways) car miles collectively"
      ],
      "topics": [
        "railways",
        "transport"
      ]
    },
    {
      "glosses": [
        "The amount paid by one road for the use of cars of another road."
      ],
      "id": "en-car_mileage-en-noun-DLP7BhDI",
      "links": [
        [
          "road",
          "road"
        ]
      ]
    }
  ],
  "word": "car mileage"
}

{
  "categories": [
    "English countable nouns",
    "English entries with incorrect language header",
    "English lemmas",
    "English multiword terms",
    "English nouns",
    "English nouns with unknown or uncertain plurals"
  ],
  "head_templates": [
    {
      "args": {
        "1": "?"
      },
      "expansion": "car mileage",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "glosses": [
        "car miles collectively"
      ],
      "links": [
        [
          "car mile",
          "car mile"
        ]
      ],
      "raw_glosses": [
        "(railways) car miles collectively"
      ],
      "topics": [
        "railways",
        "transport"
      ]
    },
    {
      "glosses": [
        "The amount paid by one road for the use of cars of another road."
      ],
      "links": [
        [
          "road",
          "road"
        ]
      ]
    }
  ],
  "word": "car mileage"
}