"Bristol onion" meaning in English

{
  "forms": [
    {
      "form": "Bristol onions",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "Bristol onion (plural Bristol onions)",
      "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",
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          "source": "w"
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          "source": "w"
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        },
        {
          "kind": "lifeform",
          "langcode": "en",
          "name": "Alliums",
          "orig": "en:Alliums",
          "parents": [
            "Amaryllis family plants",
            "Root vegetables",
            "Spices and herbs",
            "Asparagales order plants",
            "Flowers",
            "Vegetables",
            "Foods",
            "Plants",
            "Eating",
            "Food and drink",
            "Lifeforms",
            "Human behaviour",
            "All topics",
            "Life",
            "Human",
            "Fundamental",
            "Nature"
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          "source": "w"
        }
      ],
      "glosses": [
        "A species of onion, Allium sphaerocephalon, found only on the slopes of the Avon Gorge"
      ],
      "id": "en-Bristol_onion-en-noun-KUuoxl93",
      "links": [
        [
          "onion",
          "onion"
        ],
        [
          "Avon Gorge",
          "Avon Gorge"
        ]
      ],
      "synonyms": [
        {
          "word": "round-headed leek"
        }
      ]
    }
  ],
  "word": "Bristol onion"
}

{
  "forms": [
    {
      "form": "Bristol onions",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "Bristol onion (plural Bristol onions)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
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        "English entries with incorrect language header",
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        "en:Alliums"
      ],
      "glosses": [
        "A species of onion, Allium sphaerocephalon, found only on the slopes of the Avon Gorge"
      ],
      "links": [
        [
          "onion",
          "onion"
        ],
        [
          "Avon Gorge",
          "Avon Gorge"
        ]
      ]
    }
  ],
  "synonyms": [
    {
      "word": "round-headed leek"
    }
  ],
  "word": "Bristol onion"
}