"hypoelliptic operator" meaning in English

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      "form": "hypoelliptic operators",
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      "expansion": "hypoelliptic operator (plural hypoelliptic operators)",
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  "lang_code": "en",
  "pos": "noun",
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      "glosses": [
        "A differential operator that preserves mathematical smoothness."
      ],
      "id": "en-hypoelliptic_operator-en-noun-n330Wv~w",
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          "calculus",
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          "differential",
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          "smoothness",
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        "(calculus) A differential operator that preserves mathematical smoothness."
      ],
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        "calculus",
        "mathematics",
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      "wikipedia": [
        "hypoelliptic operator"
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  "word": "hypoelliptic operator"
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      "form": "hypoelliptic operators",
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      "expansion": "hypoelliptic operator (plural hypoelliptic operators)",
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  "lang_code": "en",
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        "A differential operator that preserves mathematical smoothness."
      ],
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          "calculus",
          "calculus"
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          "differential",
          "differential"
        ],
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        [
          "smoothness",
          "smoothness"
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      "raw_glosses": [
        "(calculus) A differential operator that preserves mathematical smoothness."
      ],
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        "calculus",
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  "word": "hypoelliptic operator"
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