"pollution permit system" meaning in English

{
  "forms": [
    {
      "form": "pollution permit systems",
      "tags": [
        "plural"
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      "expansion": "pollution permit system (plural pollution permit systems)",
      "name": "en-noun"
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
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      "glosses": [
        "A system aimed at controlling pollution by allocating each firm a certain amount of pollution permits which allows them to pollute up to a certain limit. If firms pollute less, they are able to sell there permits to firms that pollute more hence creating a permits market."
      ],
      "id": "en-pollution_permit_system-en-noun-c2sZJSGp"
    }
  ],
  "word": "pollution permit system"
}

{
  "forms": [
    {
      "form": "pollution permit systems",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
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      "expansion": "pollution permit system (plural pollution permit systems)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
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      ],
      "glosses": [
        "A system aimed at controlling pollution by allocating each firm a certain amount of pollution permits which allows them to pollute up to a certain limit. If firms pollute less, they are able to sell there permits to firms that pollute more hence creating a permits market."
      ]
    }
  ],
  "word": "pollution permit system"
}