"salt of vitriol" meaning in All languages combined

{
  "head_templates": [
    {
      "args": {
        "1": "-"
      },
      "expansion": "salt of vitriol (uncountable)",
      "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": "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": "Zinc",
          "orig": "en:Zinc",
          "parents": [
            "Transition metals",
            "Chemical elements",
            "Metals",
            "Matter",
            "Metallurgy",
            "Chemistry",
            "Nature",
            "Technology",
            "Sciences",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "zinc sulphate"
      ],
      "id": "en-salt_of_vitriol-en-noun-bk4FsMgd",
      "links": [
        [
          "zinc sulphate",
          "zinc sulphate"
        ]
      ],
      "raw_glosses": [
        "(obsolete) zinc sulphate"
      ],
      "tags": [
        "obsolete",
        "uncountable"
      ]
    }
  ],
  "word": "salt of vitriol"
}

{
  "head_templates": [
    {
      "args": {
        "1": "-"
      },
      "expansion": "salt of vitriol (uncountable)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "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 terms with obsolete senses",
        "English uncountable nouns",
        "en:Zinc"
      ],
      "glosses": [
        "zinc sulphate"
      ],
      "links": [
        [
          "zinc sulphate",
          "zinc sulphate"
        ]
      ],
      "raw_glosses": [
        "(obsolete) zinc sulphate"
      ],
      "tags": [
        "obsolete",
        "uncountable"
      ]
    }
  ],
  "word": "salt of vitriol"
}