"blue John" meaning in English

{
  "etymology_templates": [
    {
      "args": {
        "1": "en",
        "2": "blue"
      },
      "expansion": "blue",
      "name": "m"
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    {
      "args": {
        "1": "en",
        "2": "John"
      },
      "expansion": "John",
      "name": "m"
    }
  ],
  "etymology_text": "From blue + John.",
  "head_templates": [
    {
      "args": {
        "1": "-"
      },
      "expansion": "blue John (uncountable)",
      "name": "en-noun"
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Brewing",
          "orig": "en:Brewing",
          "parents": [
            "Alcohol production",
            "Alcoholic beverages",
            "Beverages",
            "Recreational drugs",
            "Drinking",
            "Food and drink",
            "Liquids",
            "Drugs",
            "Human behaviour",
            "All topics",
            "Matter",
            "Pharmacology",
            "Human",
            "Fundamental",
            "Chemistry",
            "Nature",
            "Biochemistry",
            "Medicine",
            "Sciences",
            "Biology"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "Afterwort, partially fermented wort."
      ],
      "id": "en-blue_John-en-noun-lno5iN2w",
      "links": [
        [
          "brewing",
          "brewing#Noun"
        ],
        [
          "Afterwort",
          "afterwort"
        ],
        [
          "wort",
          "wort"
        ]
      ],
      "raw_glosses": [
        "(obsolete, brewing) Afterwort, partially fermented wort."
      ],
      "related": [
        {
          "_dis1": "94 2 4",
          "word": "sky blue"
        }
      ],
      "synonyms": [
        {
          "_dis1": "66 9 25",
          "word": "bluejohn"
        },
        {
          "_dis1": "66 9 25",
          "word": "blue john"
        },
        {
          "_dis1": "66 9 25",
          "word": "blue-john"
        },
        {
          "_dis1": "66 9 25",
          "word": "blue-John"
        },
        {
          "_dis1": "66 9 25",
          "word": "Blue John"
        }
      ],
      "tags": [
        "obsolete",
        "uncountable"
      ],
      "topics": [
        "beverages",
        "brewing",
        "business",
        "food",
        "lifestyle",
        "manufacturing"
      ]
    },
    {
      "glosses": [
        "A semiprecious mineral mined in Derbyshire, a form of fluorite with bands of a purple-blue or yellowish colour."
      ],
      "id": "en-blue_John-en-noun-z3rD0BOn",
      "links": [
        [
          "semiprecious",
          "semiprecious"
        ],
        [
          "mineral",
          "mineral"
        ],
        [
          "fluorite",
          "fluorite"
        ]
      ],
      "tags": [
        "uncountable"
      ]
    },
    {
      "categories": [
        {
          "kind": "other",
          "name": "American English",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Regional English",
          "parents": [],
          "source": "w"
        },
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          "_dis": "27 12 61",
          "kind": "other",
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          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
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          "source": "w+disamb"
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          "_dis": "23 12 64",
          "kind": "other",
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          "_dis": "21 12 67",
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          "parents": [
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            "Entry maintenance"
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          "source": "w+disamb"
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      ],
      "examples": [
        {
          "ref": "1968, Charles Portis, True Grit",
          "text": "Lee went up front to his icebox and brought back a jar of milk. The cream had been skimmed from it. I said, “This tastes like blue-john to me.”",
          "type": "quotation"
        }
      ],
      "glosses": [
        "Skimmed milk."
      ],
      "id": "en-blue_John-en-noun-i1S-lmun",
      "links": [
        [
          "regional",
          "regional#English"
        ],
        [
          "Skimmed milk",
          "skimmed milk"
        ]
      ],
      "raw_glosses": [
        "(US regional) Skimmed milk."
      ],
      "tags": [
        "US",
        "regional",
        "uncountable"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "/ˈbluː dʒɒn/",
      "tags": [
        "UK"
      ]
    }
  ],
  "wikipedia": [
    "Derbyshire Blue John"
  ],
  "word": "blue John"
}

{
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    "English entries with incorrect language header",
    "English entries with language name categories using raw markup",
    "English eponyms",
    "English lemmas",
    "English multiword terms",
    "English nouns",
    "English terms with IPA pronunciation",
    "English terms with non-redundant non-automated sortkeys",
    "English uncountable nouns"
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  "etymology_templates": [
    {
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        "2": "blue"
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      "expansion": "blue",
      "name": "m"
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    {
      "args": {
        "1": "en",
        "2": "John"
      },
      "expansion": "John",
      "name": "m"
    }
  ],
  "etymology_text": "From blue + John.",
  "head_templates": [
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        "1": "-"
      },
      "expansion": "blue John (uncountable)",
      "name": "en-noun"
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "related": [
    {
      "word": "sky blue"
    }
  ],
  "senses": [
    {
      "categories": [
        "English terms with obsolete senses",
        "en:Brewing"
      ],
      "glosses": [
        "Afterwort, partially fermented wort."
      ],
      "links": [
        [
          "brewing",
          "brewing#Noun"
        ],
        [
          "Afterwort",
          "afterwort"
        ],
        [
          "wort",
          "wort"
        ]
      ],
      "raw_glosses": [
        "(obsolete, brewing) Afterwort, partially fermented wort."
      ],
      "tags": [
        "obsolete",
        "uncountable"
      ],
      "topics": [
        "beverages",
        "brewing",
        "business",
        "food",
        "lifestyle",
        "manufacturing"
      ]
    },
    {
      "glosses": [
        "A semiprecious mineral mined in Derbyshire, a form of fluorite with bands of a purple-blue or yellowish colour."
      ],
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        [
          "semiprecious",
          "semiprecious"
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        [
          "mineral",
          "mineral"
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          "fluorite",
          "fluorite"
        ]
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      "tags": [
        "uncountable"
      ]
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        "English terms with quotations",
        "Quotation templates to be cleaned",
        "Regional English"
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      "examples": [
        {
          "ref": "1968, Charles Portis, True Grit",
          "text": "Lee went up front to his icebox and brought back a jar of milk. The cream had been skimmed from it. I said, “This tastes like blue-john to me.”",
          "type": "quotation"
        }
      ],
      "glosses": [
        "Skimmed milk."
      ],
      "links": [
        [
          "regional",
          "regional#English"
        ],
        [
          "Skimmed milk",
          "skimmed milk"
        ]
      ],
      "raw_glosses": [
        "(US regional) Skimmed milk."
      ],
      "tags": [
        "US",
        "regional",
        "uncountable"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "/ˈbluː dʒɒn/",
      "tags": [
        "UK"
      ]
    }
  ],
  "synonyms": [
    {
      "word": "bluejohn"
    },
    {
      "word": "blue john"
    },
    {
      "word": "blue-john"
    },
    {
      "word": "blue-John"
    },
    {
      "word": "Blue John"
    }
  ],
  "wikipedia": [
    "Derbyshire Blue John"
  ],
  "word": "blue John"
}