"fairies' horse" meaning in English

{
  "forms": [
    {
      "form": "fairies' horses",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "head": "fairies' horse"
      },
      "expansion": "fairies' horse (plural fairies' horses)",
      "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"
        }
      ],
      "examples": [
        {
          "ref": "1940, Rosetta E. Clarkson, Green Enchantments: The Magic Spell of Gardens, The Macmillan Company, page 267",
          "text": "As we all know, witches ride through the air on a broom, but sometimes their means of locomotion was a bulrush, a branch of thorn, mullein stalks, cornstalk, or ragweed, called fairies' horse in Ireland.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "ragweed"
      ],
      "id": "en-fairies'_horse-en-noun-ZPMQlOYj",
      "links": [
        [
          "ragweed",
          "ragweed"
        ]
      ]
    }
  ],
  "word": "fairies' horse"
}

{
  "forms": [
    {
      "form": "fairies' horses",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "head": "fairies' horse"
      },
      "expansion": "fairies' horse (plural fairies' horses)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "English terms with quotations"
      ],
      "examples": [
        {
          "ref": "1940, Rosetta E. Clarkson, Green Enchantments: The Magic Spell of Gardens, The Macmillan Company, page 267",
          "text": "As we all know, witches ride through the air on a broom, but sometimes their means of locomotion was a bulrush, a branch of thorn, mullein stalks, cornstalk, or ragweed, called fairies' horse in Ireland.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "ragweed"
      ],
      "links": [
        [
          "ragweed",
          "ragweed"
        ]
      ]
    }
  ],
  "word": "fairies' horse"
}