"bound water" meaning in English

{
  "antonyms": [
    {
      "word": "free water"
    }
  ],
  "forms": [
    {
      "form": "bound waters",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "~"
      },
      "expansion": "bound water (countable and uncountable, plural bound waters)",
      "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"
          ],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Hydrology",
          "orig": "en:Hydrology",
          "parents": [
            "Earth sciences",
            "Water",
            "Sciences",
            "Liquids",
            "All topics",
            "Matter",
            "Fundamental",
            "Chemistry",
            "Nature"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "Water that is bound to an inorganic surface."
      ],
      "id": "en-bound_water-en-noun-GS7CFRfA",
      "links": [
        [
          "hydrology",
          "hydrology"
        ],
        [
          "bound",
          "bound"
        ],
        [
          "inorganic",
          "inorganic"
        ],
        [
          "surface",
          "surface"
        ]
      ],
      "raw_glosses": [
        "(hydrology) Water that is bound to an inorganic surface."
      ],
      "tags": [
        "countable",
        "uncountable"
      ],
      "topics": [
        "geography",
        "hydrology",
        "natural-sciences"
      ]
    }
  ],
  "word": "bound water"
}

{
  "antonyms": [
    {
      "word": "free water"
    }
  ],
  "forms": [
    {
      "form": "bound waters",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "~"
      },
      "expansion": "bound water (countable and uncountable, plural bound waters)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "English uncountable nouns",
        "en:Hydrology"
      ],
      "glosses": [
        "Water that is bound to an inorganic surface."
      ],
      "links": [
        [
          "hydrology",
          "hydrology"
        ],
        [
          "bound",
          "bound"
        ],
        [
          "inorganic",
          "inorganic"
        ],
        [
          "surface",
          "surface"
        ]
      ],
      "raw_glosses": [
        "(hydrology) Water that is bound to an inorganic surface."
      ],
      "tags": [
        "countable",
        "uncountable"
      ],
      "topics": [
        "geography",
        "hydrology",
        "natural-sciences"
      ]
    }
  ],
  "word": "bound water"
}