"four thieves' vinegar" meaning in English

{
  "etymology_text": "From the story that thieves, by using it, were enabled to plunder, with impunity to health, in the great plague at London. Possibly originally a corruption of \"Forthave's vinegar\", Richard Forthave being the publisher of an early recipe.",
  "head_templates": [
    {
      "args": {
        "1": "-",
        "head": "four thieves' vinegar"
      },
      "expansion": "four thieves' vinegar (uncountable)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "British English",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "Vinegar mixed with camphor and essential oils, formerly used as medicine."
      ],
      "id": "en-four_thieves'_vinegar-en-noun-Wuy3MijG",
      "links": [
        [
          "camphor",
          "camphor"
        ],
        [
          "essential oils",
          "essential oils"
        ],
        [
          "medicine",
          "medicine"
        ]
      ],
      "raw_glosses": [
        "(UK, archaic) Vinegar mixed with camphor and essential oils, formerly used as medicine."
      ],
      "synonyms": [
        {
          "word": "Marseilles vinegar"
        },
        {
          "word": "thieves' vinegar"
        }
      ],
      "tags": [
        "UK",
        "archaic",
        "uncountable"
      ]
    }
  ],
  "word": "four thieves' vinegar"
}

{
  "etymology_text": "From the story that thieves, by using it, were enabled to plunder, with impunity to health, in the great plague at London. Possibly originally a corruption of \"Forthave's vinegar\", Richard Forthave being the publisher of an early recipe.",
  "head_templates": [
    {
      "args": {
        "1": "-",
        "head": "four thieves' vinegar"
      },
      "expansion": "four thieves' vinegar (uncountable)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "British English",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "English terms with archaic senses",
        "English uncountable nouns"
      ],
      "glosses": [
        "Vinegar mixed with camphor and essential oils, formerly used as medicine."
      ],
      "links": [
        [
          "camphor",
          "camphor"
        ],
        [
          "essential oils",
          "essential oils"
        ],
        [
          "medicine",
          "medicine"
        ]
      ],
      "raw_glosses": [
        "(UK, archaic) Vinegar mixed with camphor and essential oils, formerly used as medicine."
      ],
      "tags": [
        "UK",
        "archaic",
        "uncountable"
      ]
    }
  ],
  "synonyms": [
    {
      "word": "Marseilles vinegar"
    },
    {
      "word": "thieves' vinegar"
    }
  ],
  "word": "four thieves' vinegar"
}