"running sand" meaning in English

{
  "head_templates": [
    {
      "args": {
        "1": "-"
      },
      "expansion": "running sand (uncountable)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
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          "source": "w"
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          "source": "w"
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          "parents": [],
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        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Construction",
          "orig": "en:Construction",
          "parents": [
            "Architecture",
            "Engineering",
            "Applied sciences",
            "Art",
            "Technology",
            "Sciences",
            "Culture",
            "All topics",
            "Society",
            "Fundamental"
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          "source": "w"
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      "examples": [
        {
          "ref": "1946 January and February, “Notes and News: Demolition of Rhydyfelin Viaduct”, in Railway Magazine, page 53:",
          "text": "During the construction of the viaduct, the sinking of the caissons in the river bed caused much difficulty to the engineer and contractors, as a bed of running sand was encountered; in consequence, the expenditure for these foundations proved almost prohibitive.",
          "type": "quote"
        }
      ],
      "glosses": [
        "Saturated sand which flows into an excavation or void due to water pressure."
      ],
      "id": "en-running_sand-en-noun-NygdMAIK",
      "links": [
        [
          "construction",
          "construction"
        ],
        [
          "Saturated",
          "saturated"
        ],
        [
          "excavation",
          "excavation"
        ],
        [
          "water",
          "water"
        ],
        [
          "pressure",
          "pressure"
        ]
      ],
      "raw_glosses": [
        "(construction) Saturated sand which flows into an excavation or void due to water pressure."
      ],
      "tags": [
        "uncountable"
      ],
      "topics": [
        "business",
        "construction",
        "manufacturing"
      ]
    }
  ],
  "word": "running sand"
}

{
  "head_templates": [
    {
      "args": {
        "1": "-"
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      "expansion": "running sand (uncountable)",
      "name": "en-noun"
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
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        "English lemmas",
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        "en:Construction"
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      "examples": [
        {
          "ref": "1946 January and February, “Notes and News: Demolition of Rhydyfelin Viaduct”, in Railway Magazine, page 53:",
          "text": "During the construction of the viaduct, the sinking of the caissons in the river bed caused much difficulty to the engineer and contractors, as a bed of running sand was encountered; in consequence, the expenditure for these foundations proved almost prohibitive.",
          "type": "quote"
        }
      ],
      "glosses": [
        "Saturated sand which flows into an excavation or void due to water pressure."
      ],
      "links": [
        [
          "construction",
          "construction"
        ],
        [
          "Saturated",
          "saturated"
        ],
        [
          "excavation",
          "excavation"
        ],
        [
          "water",
          "water"
        ],
        [
          "pressure",
          "pressure"
        ]
      ],
      "raw_glosses": [
        "(construction) Saturated sand which flows into an excavation or void due to water pressure."
      ],
      "tags": [
        "uncountable"
      ],
      "topics": [
        "business",
        "construction",
        "manufacturing"
      ]
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  ],
  "word": "running sand"
}