"Six Sigma" meaning in English

{
  "etymology_text": "A reference to the fraction of a normal curve that lies within six standard deviations of the mean, used to represent a defect rate.",
  "head_templates": [
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        "head": "Six Sigma"
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  "lang": "English",
  "lang_code": "en",
  "pos": "name",
  "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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        {
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        {
          "kind": "topical",
          "langcode": "en",
          "name": "Business",
          "orig": "en:Business",
          "parents": [
            "Economics",
            "Society",
            "Social sciences",
            "All topics",
            "Sciences",
            "Fundamental"
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        }
      ],
      "glosses": [
        "A set of techniques and tools for process improvement."
      ],
      "id": "en-Six_Sigma-en-name-BMJgs50v",
      "links": [
        [
          "business",
          "business"
        ]
      ],
      "raw_glosses": [
        "(business) A set of techniques and tools for process improvement."
      ],
      "related": [
        {
          "word": "statistically significant"
        }
      ],
      "topics": [
        "business"
      ],
      "wikipedia": [
        "Six Sigma"
      ]
    }
  ],
  "word": "Six Sigma"
}

{
  "etymology_text": "A reference to the fraction of a normal curve that lies within six standard deviations of the mean, used to represent a defect rate.",
  "head_templates": [
    {
      "args": {
        "head": "Six Sigma"
      },
      "expansion": "Six Sigma",
      "name": "en-proper noun"
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  "lang": "English",
  "lang_code": "en",
  "pos": "name",
  "related": [
    {
      "word": "statistically significant"
    }
  ],
  "senses": [
    {
      "categories": [
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English proper nouns",
        "English uncountable nouns",
        "Pages with 1 entry",
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        "en:Business"
      ],
      "glosses": [
        "A set of techniques and tools for process improvement."
      ],
      "links": [
        [
          "business",
          "business"
        ]
      ],
      "raw_glosses": [
        "(business) A set of techniques and tools for process improvement."
      ],
      "topics": [
        "business"
      ],
      "wikipedia": [
        "Six Sigma"
      ]
    }
  ],
  "word": "Six Sigma"
}