"coal roller" meaning in English

{
  "forms": [
    {
      "form": "coal rollers",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "coal roller (plural coal rollers)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Automotive",
          "orig": "en:Automotive",
          "parents": [
            "Transport",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "One that rolls coal; one that produces copious amounts of partially burnt fuel as black smoke in automotive exhaust on purpose."
      ],
      "id": "en-coal_roller-en-noun-2HtUbd2Z",
      "links": [
        [
          "automotive",
          "automotive"
        ],
        [
          "rolls coal",
          "roll coal#English"
        ]
      ],
      "raw_glosses": [
        "(automotive) One that rolls coal; one that produces copious amounts of partially burnt fuel as black smoke in automotive exhaust on purpose."
      ],
      "related": [
        {
          "word": "coal-rolled"
        },
        {
          "word": "coal-rolling"
        },
        {
          "word": "roll coal"
        }
      ],
      "synonyms": [
        {
          "word": "coal-roller"
        }
      ],
      "topics": [
        "automotive",
        "transport",
        "vehicles"
      ]
    }
  ],
  "word": "coal roller"
}

{
  "forms": [
    {
      "form": "coal rollers",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "coal roller (plural coal rollers)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "related": [
    {
      "word": "coal-rolled"
    },
    {
      "word": "coal-rolling"
    },
    {
      "word": "roll coal"
    }
  ],
  "senses": [
    {
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "en:Automotive"
      ],
      "glosses": [
        "One that rolls coal; one that produces copious amounts of partially burnt fuel as black smoke in automotive exhaust on purpose."
      ],
      "links": [
        [
          "automotive",
          "automotive"
        ],
        [
          "rolls coal",
          "roll coal#English"
        ]
      ],
      "raw_glosses": [
        "(automotive) One that rolls coal; one that produces copious amounts of partially burnt fuel as black smoke in automotive exhaust on purpose."
      ],
      "topics": [
        "automotive",
        "transport",
        "vehicles"
      ]
    }
  ],
  "synonyms": [
    {
      "word": "coal-roller"
    }
  ],
  "word": "coal roller"
}