"underdetection" meaning in English

{
  "etymology_templates": [
    {
      "args": {
        "1": "en",
        "2": "under",
        "3": "detection"
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      "expansion": "under- + detection",
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    }
  ],
  "etymology_text": "under- + detection",
  "head_templates": [
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      "args": {
        "1": "-"
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      "expansion": "underdetection (uncountable)",
      "name": "en-noun"
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
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          "source": "w"
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          "name": "English terms prefixed with under-",
          "parents": [],
          "source": "w"
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      "examples": [
        {
          "ref": "2009 January 13, Nicholas Bakalar, “Prognosis: Left Behind in Prostate Cancer Screening”, in New York Times",
          "text": "But this study says that in these very disadvantaged men, there is underdetection and undertreatment, that the cancers are not being found early enough.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "Detection at excessively low levels, or at levels lower than are actually the case"
      ],
      "id": "en-underdetection-en-noun-kK9QbPsf",
      "links": [
        [
          "Detection",
          "detection"
        ]
      ],
      "related": [
        {
          "word": "underdetect"
        }
      ],
      "tags": [
        "uncountable"
      ]
    }
  ],
  "word": "underdetection"
}

{
  "etymology_templates": [
    {
      "args": {
        "1": "en",
        "2": "under",
        "3": "detection"
      },
      "expansion": "under- + detection",
      "name": "prefix"
    }
  ],
  "etymology_text": "under- + detection",
  "head_templates": [
    {
      "args": {
        "1": "-"
      },
      "expansion": "underdetection (uncountable)",
      "name": "en-noun"
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  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "related": [
    {
      "word": "underdetect"
    }
  ],
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        {
          "ref": "2009 January 13, Nicholas Bakalar, “Prognosis: Left Behind in Prostate Cancer Screening”, in New York Times",
          "text": "But this study says that in these very disadvantaged men, there is underdetection and undertreatment, that the cancers are not being found early enough.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "Detection at excessively low levels, or at levels lower than are actually the case"
      ],
      "links": [
        [
          "Detection",
          "detection"
        ]
      ],
      "tags": [
        "uncountable"
      ]
    }
  ],
  "word": "underdetection"
}