"oak apple" meaning in English

{
  "forms": [
    {
      "form": "oak apples",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "oak apple (plural oak apples)",
      "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"
        },
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          "name": "English entries with topic categories using raw markup",
          "parents": [
            "Entries with topic categories using raw markup",
            "Entry maintenance"
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          "source": "w"
        },
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          "kind": "other",
          "name": "English terms with non-redundant non-automated sortkeys",
          "parents": [
            "Terms with non-redundant non-automated sortkeys",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "lifeform",
          "langcode": "en",
          "name": "Hymenopterans",
          "orig": "en:Hymenopterans",
          "parents": [
            "Insects",
            "Arthropods",
            "Animals",
            "Lifeforms",
            "All topics",
            "Life",
            "Fundamental",
            "Nature"
          ],
          "source": "w"
        },
        {
          "kind": "lifeform",
          "langcode": "en",
          "name": "Oaks",
          "orig": "en:Oaks",
          "parents": [
            "Beech family plants",
            "Trees",
            "Fagales order plants",
            "Plants",
            "Shrubs",
            "Lifeforms",
            "All topics",
            "Life",
            "Fundamental",
            "Nature"
          ],
          "source": "w"
        }
      ],
      "derived": [
        {
          "word": "Oak Apple Day"
        }
      ],
      "examples": [
        {
          "ref": "1665, Robert Hooke, Micrographia, section XXV",
          "text": "[T]he small Apples which I have often observ'd to grow on the leaves of an Oak call'd Oak-apples […] are nothing but the Matrices of an Insect, as I elsewhere show.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "A spherical type of oak gall, produced by an oak gall wasp (tribe Cynipini)."
      ],
      "id": "en-oak_apple-en-noun-2uBswBVp",
      "links": [
        [
          "oak gall",
          "oak gall"
        ],
        [
          "tribe",
          "tribe"
        ]
      ],
      "synonyms": [
        {
          "word": "oak-apple"
        }
      ]
    }
  ],
  "word": "oak apple"
}

{
  "derived": [
    {
      "word": "Oak Apple Day"
    }
  ],
  "forms": [
    {
      "form": "oak apples",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "oak apple (plural oak apples)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "English countable nouns",
        "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 quotations",
        "Entries missing English vernacular names of taxa",
        "Entries using missing taxonomic name (tribe)",
        "Quotation templates to be cleaned",
        "en:Hymenopterans",
        "en:Oaks"
      ],
      "examples": [
        {
          "ref": "1665, Robert Hooke, Micrographia, section XXV",
          "text": "[T]he small Apples which I have often observ'd to grow on the leaves of an Oak call'd Oak-apples […] are nothing but the Matrices of an Insect, as I elsewhere show.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "A spherical type of oak gall, produced by an oak gall wasp (tribe Cynipini)."
      ],
      "links": [
        [
          "oak gall",
          "oak gall"
        ],
        [
          "tribe",
          "tribe"
        ]
      ]
    }
  ],
  "synonyms": [
    {
      "word": "oak-apple"
    }
  ],
  "word": "oak apple"
}