"natural function" meaning in English

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    {
      "form": "natural functions",
      "tags": [
        "plural"
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    }
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      "expansion": "natural function (plural natural functions)",
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
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          "name": "English entries with incorrect language header",
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        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Functions",
          "orig": "en:Functions",
          "parents": [
            "Algebra",
            "Calculus",
            "Geometry",
            "Mathematical analysis",
            "Mathematics",
            "Formal sciences",
            "Sciences",
            "All topics",
            "Fundamental"
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      ],
      "glosses": [
        "An ordinary trigonometric function"
      ],
      "id": "en-natural_function-en-noun-ccXSJQMR",
      "links": [
        [
          "mathematics",
          "mathematics"
        ],
        [
          "trigonometric function",
          "trigonometric function"
        ]
      ],
      "raw_glosses": [
        "(mathematics) An ordinary trigonometric function"
      ],
      "topics": [
        "mathematics",
        "sciences"
      ]
    }
  ],
  "word": "natural function"
}

{
  "forms": [
    {
      "form": "natural functions",
      "tags": [
        "plural"
      ]
    }
  ],
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      "expansion": "natural function (plural natural functions)",
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        "en:Functions",
        "en:Mathematics"
      ],
      "glosses": [
        "An ordinary trigonometric function"
      ],
      "links": [
        [
          "mathematics",
          "mathematics"
        ],
        [
          "trigonometric function",
          "trigonometric function"
        ]
      ],
      "raw_glosses": [
        "(mathematics) An ordinary trigonometric function"
      ],
      "topics": [
        "mathematics",
        "sciences"
      ]
    }
  ],
  "word": "natural function"
}