"mail car" meaning in English

{
  "forms": [
    {
      "form": "mail cars",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "mail car (plural mail cars)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "American English",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English entries with topic categories using raw markup",
          "parents": [
            "Entries with topic categories using raw markup",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English terms with non-redundant non-automated sortkeys",
          "parents": [
            "Terms with non-redundant non-automated sortkeys",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Post",
          "orig": "en:Post",
          "parents": [
            "Communication",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Rail transportation",
          "orig": "en:Rail transportation",
          "parents": [
            "Transport",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "a railroad car in which mail is carried and sorted."
      ],
      "id": "en-mail_car-en-noun-dhobgfAc",
      "links": [
        [
          "rail transport",
          "rail transport"
        ],
        [
          "railroad car",
          "railroad car"
        ]
      ],
      "raw_glosses": [
        "(rail transport, US) a railroad car in which mail is carried and sorted."
      ],
      "synonyms": [
        {
          "tags": [
            "UK"
          ],
          "word": "travelling post office"
        }
      ],
      "tags": [
        "US"
      ],
      "topics": [
        "rail-transport",
        "railways",
        "transport"
      ],
      "translations": [
        {
          "code": "fr",
          "lang": "French",
          "sense": "type of railway car",
          "tags": [
            "masculine"
          ],
          "word": "wagon-poste"
        }
      ]
    }
  ],
  "word": "mail car"
}

{
  "forms": [
    {
      "form": "mail cars",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "mail car (plural mail cars)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "American English",
        "English countable nouns",
        "English entries with incorrect language header",
        "English entries with topic categories using raw markup",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "English terms with non-redundant non-automated sortkeys",
        "en:Post",
        "en:Rail transportation"
      ],
      "glosses": [
        "a railroad car in which mail is carried and sorted."
      ],
      "links": [
        [
          "rail transport",
          "rail transport"
        ],
        [
          "railroad car",
          "railroad car"
        ]
      ],
      "raw_glosses": [
        "(rail transport, US) a railroad car in which mail is carried and sorted."
      ],
      "tags": [
        "US"
      ],
      "topics": [
        "rail-transport",
        "railways",
        "transport"
      ]
    }
  ],
  "synonyms": [
    {
      "tags": [
        "UK"
      ],
      "word": "travelling post office"
    }
  ],
  "translations": [
    {
      "code": "fr",
      "lang": "French",
      "sense": "type of railway car",
      "tags": [
        "masculine"
      ],
      "word": "wagon-poste"
    }
  ],
  "word": "mail car"
}