"magic mud" meaning in English

{
  "head_templates": [
    {
      "args": {
        "1": "-"
      },
      "expansion": "magic mud (uncountable)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "glosses": [
        "A mixture of refractory materials used in casting metal."
      ],
      "id": "en-magic_mud-en-noun-7WsjI7yI",
      "links": [
        [
          "refractory",
          "refractory"
        ]
      ],
      "tags": [
        "uncountable"
      ]
    },
    {
      "categories": [
        {
          "_dis": "9 63 28",
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w+disamb"
        },
        {
          "_dis": "13 61 25",
          "kind": "other",
          "name": "English entries with topic categories using raw markup",
          "parents": [
            "Entries with topic categories using raw markup",
            "Entry maintenance"
          ],
          "source": "w+disamb"
        },
        {
          "_dis": "10 62 27",
          "kind": "other",
          "name": "English terms with non-redundant non-automated sortkeys",
          "parents": [
            "Terms with non-redundant non-automated sortkeys",
            "Entry maintenance"
          ],
          "source": "w+disamb"
        }
      ],
      "glosses": [
        "A semi-liquid substance made of cornstarch and water, used in children's experiments."
      ],
      "id": "en-magic_mud-en-noun-zFJdZMGO",
      "links": [
        [
          "cornstarch",
          "cornstarch"
        ]
      ],
      "tags": [
        "uncountable"
      ]
    },
    {
      "categories": [
        {
          "_dis": "6 39 55",
          "kind": "topical",
          "langcode": "en",
          "name": "Baseball",
          "orig": "en:Baseball",
          "parents": [
            "Ball games",
            "Sports",
            "Human activity",
            "Human behaviour",
            "Human",
            "All topics",
            "Fundamental"
          ],
          "source": "w+disamb"
        }
      ],
      "glosses": [
        "A substance used to treat baseballs before they are put into professional play, to provide a firmer grip and better control."
      ],
      "id": "en-magic_mud-en-noun-GBa-QyrE",
      "links": [
        [
          "baseball",
          "baseball"
        ],
        [
          "grip",
          "grip"
        ]
      ],
      "tags": [
        "uncountable"
      ]
    }
  ],
  "word": "magic mud"
}

{
  "categories": [
    "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",
    "English uncountable nouns",
    "en:Baseball"
  ],
  "head_templates": [
    {
      "args": {
        "1": "-"
      },
      "expansion": "magic mud (uncountable)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "glosses": [
        "A mixture of refractory materials used in casting metal."
      ],
      "links": [
        [
          "refractory",
          "refractory"
        ]
      ],
      "tags": [
        "uncountable"
      ]
    },
    {
      "glosses": [
        "A semi-liquid substance made of cornstarch and water, used in children's experiments."
      ],
      "links": [
        [
          "cornstarch",
          "cornstarch"
        ]
      ],
      "tags": [
        "uncountable"
      ]
    },
    {
      "glosses": [
        "A substance used to treat baseballs before they are put into professional play, to provide a firmer grip and better control."
      ],
      "links": [
        [
          "baseball",
          "baseball"
        ],
        [
          "grip",
          "grip"
        ]
      ],
      "tags": [
        "uncountable"
      ]
    }
  ],
  "word": "magic mud"
}