"millrun" meaning in English

{
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        "1": "en",
        "2": "mill",
        "3": "run"
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      "expansion": "mill + run",
      "name": "compound"
    }
  ],
  "etymology_text": "mill + run",
  "forms": [
    {
      "form": "millruns",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "millrun (plural millruns)",
      "name": "en-noun"
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
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          "source": "w"
        },
        {
          "kind": "place",
          "langcode": "en",
          "name": "Bodies of water",
          "orig": "en:Bodies of water",
          "parents": [
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            "Water",
            "Earth",
            "Places",
            "Liquids",
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          "source": "w"
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      ],
      "glosses": [
        "Synonym of mill race"
      ],
      "id": "en-millrun-en-noun-bEbX5UvI",
      "links": [
        [
          "mill race",
          "mill race#English"
        ]
      ],
      "synonyms": [
        {
          "tags": [
            "synonym",
            "synonym-of"
          ],
          "word": "mill race"
        }
      ]
    }
  ],
  "word": "millrun"
}

{
  "etymology_templates": [
    {
      "args": {
        "1": "en",
        "2": "mill",
        "3": "run"
      },
      "expansion": "mill + run",
      "name": "compound"
    }
  ],
  "etymology_text": "mill + run",
  "forms": [
    {
      "form": "millruns",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "millrun (plural millruns)",
      "name": "en-noun"
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  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
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        "English countable nouns",
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        "en:Bodies of water"
      ],
      "glosses": [
        "Synonym of mill race"
      ],
      "links": [
        [
          "mill race",
          "mill race#English"
        ]
      ],
      "synonyms": [
        {
          "tags": [
            "synonym",
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          ],
          "word": "mill race"
        }
      ]
    }
  ],
  "word": "millrun"
}