"coal ball" meaning in English

{
  "forms": [
    {
      "form": "coal balls",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "coal ball (plural coal balls)",
      "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": "other",
          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Coal",
          "orig": "en:Coal",
          "parents": [
            "Fossil fuels",
            "Carbon",
            "Energy",
            "Natural resources",
            "Carbon group elements",
            "Nature",
            "Matter",
            "Chemical elements",
            "All topics",
            "Chemistry",
            "Fundamental",
            "Sciences"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "A nodule of plant material permeated with minerals found mostly in bituminous and anthracite coal seams"
      ],
      "id": "en-coal_ball-en-noun-31DHKkDP",
      "links": [
        [
          "nodule",
          "nodule"
        ],
        [
          "plant",
          "plant"
        ],
        [
          "mineral",
          "mineral"
        ],
        [
          "bituminous",
          "bituminous"
        ],
        [
          "anthracite",
          "anthracite"
        ]
      ],
      "synonyms": [
        {
          "word": "coalball"
        }
      ],
      "wikipedia": [
        "coal ball"
      ]
    }
  ],
  "word": "coal ball"
}

{
  "forms": [
    {
      "form": "coal balls",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "coal ball (plural coal balls)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "Pages with 1 entry",
        "Pages with entries",
        "en:Coal"
      ],
      "glosses": [
        "A nodule of plant material permeated with minerals found mostly in bituminous and anthracite coal seams"
      ],
      "links": [
        [
          "nodule",
          "nodule"
        ],
        [
          "plant",
          "plant"
        ],
        [
          "mineral",
          "mineral"
        ],
        [
          "bituminous",
          "bituminous"
        ],
        [
          "anthracite",
          "anthracite"
        ]
      ],
      "wikipedia": [
        "coal ball"
      ]
    }
  ],
  "synonyms": [
    {
      "word": "coalball"
    }
  ],
  "word": "coal ball"
}