"rag books" meaning in English

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  "lang_code": "en",
  "pos": "noun",
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      "form_of": [
        {
          "word": "rag book"
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        "plural of rag book"
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      "id": "en-rag_books-en-noun-sqVmy2WF",
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  "word": "rag books"
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  "lang_code": "en",
  "pos": "noun",
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      "form_of": [
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  "word": "rag books"
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