"oak leather" meaning in English

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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
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      "glosses": [
        "Fungal mycelia in the fissures of old oak trees."
      ],
      "id": "en-oak_leather-en-noun-IWmrabSd",
      "links": [
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          "Fungal",
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          "mycelia",
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          "fissure",
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        [
          "oak",
          "oak"
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          "tree",
          "tree"
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        "uncountable"
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  "word": "oak leather"
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
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        "Fungal mycelia in the fissures of old oak trees."
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          "oak",
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          "tree"
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  "word": "oak leather"
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