"decadist" meaning in English

{
  "etymology_templates": [
    {
      "args": {
        "1": "en",
        "2": "decade",
        "3": "ist"
      },
      "expansion": "decade + -ist",
      "name": "suffix"
    }
  ],
  "etymology_text": "From decade + -ist.",
  "forms": [
    {
      "form": "decadists",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "decadist (plural decadists)",
      "name": "en-noun"
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  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
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        {
          "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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          "name": "English terms suffixed with -ist",
          "parents": [],
          "source": "w"
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        {
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          "parents": [],
          "source": "w"
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          "source": "w"
        }
      ],
      "examples": [
        {
          "text": "Livy was a decadist.",
          "type": "example"
        }
      ],
      "glosses": [
        "A writer of a book divided into decades (ten parts)."
      ],
      "id": "en-decadist-en-noun-ortgxjGN",
      "links": [
        [
          "writer",
          "writer"
        ],
        [
          "book",
          "book"
        ],
        [
          "decade",
          "decade"
        ]
      ]
    }
  ],
  "word": "decadist"
}

{
  "etymology_templates": [
    {
      "args": {
        "1": "en",
        "2": "decade",
        "3": "ist"
      },
      "expansion": "decade + -ist",
      "name": "suffix"
    }
  ],
  "etymology_text": "From decade + -ist.",
  "forms": [
    {
      "form": "decadists",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "decadist (plural decadists)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
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        "Pages with entries"
      ],
      "examples": [
        {
          "text": "Livy was a decadist.",
          "type": "example"
        }
      ],
      "glosses": [
        "A writer of a book divided into decades (ten parts)."
      ],
      "links": [
        [
          "writer",
          "writer"
        ],
        [
          "book",
          "book"
        ],
        [
          "decade",
          "decade"
        ]
      ]
    }
  ],
  "word": "decadist"
}