"weight stack" meaning in English

{
  "forms": [
    {
      "form": "weight stacks",
      "tags": [
        "plural"
      ]
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    {
      "args": {},
      "expansion": "weight stack (plural weight stacks)",
      "name": "en-noun"
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
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      ],
      "glosses": [
        "a block of calibrated weight, often used in an exercising machine"
      ],
      "id": "en-weight_stack-en-noun-fj4MpcDF",
      "translations": [
        {
          "code": "nl",
          "lang": "Dutch",
          "sense": "a block of calibrated weight, often used in an exercising machine",
          "tags": [
            "neuter"
          ],
          "word": "gewichtsblok"
        }
      ]
    }
  ],
  "word": "weight stack"
}

{
  "forms": [
    {
      "form": "weight stacks",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "weight stack (plural weight stacks)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
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        "English multiword terms",
        "English nouns",
        "Entries with translation boxes",
        "Pages with 1 entry",
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      ],
      "glosses": [
        "a block of calibrated weight, often used in an exercising machine"
      ]
    }
  ],
  "translations": [
    {
      "code": "nl",
      "lang": "Dutch",
      "sense": "a block of calibrated weight, often used in an exercising machine",
      "tags": [
        "neuter"
      ],
      "word": "gewichtsblok"
    }
  ],
  "word": "weight stack"
}