"air reservoir" meaning in English

{
  "forms": [
    {
      "form": "air reservoirs",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "air reservoir (plural air reservoirs)",
      "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": "other",
          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Containers",
          "orig": "en:Containers",
          "parents": [
            "Tools",
            "Technology",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "examples": [
        {
          "ref": "1960 July, “The first G.E.C. 25 kV. a.c. electric locomotives for B.R.”, in Trains Illustrated, page 419:",
          "text": "Batteries, weak-field resistors and air reservoirs are slung under the main frame between the bogies.",
          "type": "quote"
        }
      ],
      "glosses": [
        "A container, such as a pressurised tank, for holding compressed air."
      ],
      "id": "en-air_reservoir-en-noun-p9zOU1pg",
      "links": [
        [
          "container",
          "container"
        ],
        [
          "pressurised",
          "pressurised"
        ],
        [
          "tank",
          "tank"
        ],
        [
          "compressed air",
          "compressed air"
        ]
      ]
    }
  ],
  "word": "air reservoir"
}

{
  "forms": [
    {
      "form": "air reservoirs",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "air reservoir (plural air reservoirs)",
      "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 terms with quotations",
        "Pages with 1 entry",
        "Pages with entries",
        "en:Containers"
      ],
      "examples": [
        {
          "ref": "1960 July, “The first G.E.C. 25 kV. a.c. electric locomotives for B.R.”, in Trains Illustrated, page 419:",
          "text": "Batteries, weak-field resistors and air reservoirs are slung under the main frame between the bogies.",
          "type": "quote"
        }
      ],
      "glosses": [
        "A container, such as a pressurised tank, for holding compressed air."
      ],
      "links": [
        [
          "container",
          "container"
        ],
        [
          "pressurised",
          "pressurised"
        ],
        [
          "tank",
          "tank"
        ],
        [
          "compressed air",
          "compressed air"
        ]
      ]
    }
  ],
  "word": "air reservoir"
}