"Cartesian diver" meaning in English

{
  "forms": [
    {
      "form": "Cartesian divers",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "Cartesian diver (plural Cartesian divers)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
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      ],
      "glosses": [
        "A toy or a science experiment in which the \"diver\", usually a small glass tube, is placed in a larger container with flexible walls. The \"diver\" falls when the large container is pressed, and rises as the pressure is released."
      ],
      "id": "en-Cartesian_diver-en-noun-QkO6nj2H",
      "links": [
        [
          "toy",
          "toy"
        ]
      ],
      "synonyms": [
        {
          "word": "bottle imp"
        },
        {
          "word": "Cartesian devil"
        }
      ],
      "wikipedia": [
        "Cartesian diver"
      ]
    }
  ],
  "word": "Cartesian diver"
}

{
  "forms": [
    {
      "form": "Cartesian divers",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "Cartesian diver (plural Cartesian divers)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English entries with language name categories using raw markup",
        "English eponyms",
        "English lemmas",
        "English multiword terms",
        "English nouns",
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      ],
      "glosses": [
        "A toy or a science experiment in which the \"diver\", usually a small glass tube, is placed in a larger container with flexible walls. The \"diver\" falls when the large container is pressed, and rises as the pressure is released."
      ],
      "links": [
        [
          "toy",
          "toy"
        ]
      ],
      "wikipedia": [
        "Cartesian diver"
      ]
    }
  ],
  "synonyms": [
    {
      "word": "bottle imp"
    },
    {
      "word": "Cartesian devil"
    }
  ],
  "word": "Cartesian diver"
}