"Critical Mass" meaning in English

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      "name": "en-proper noun"
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  "lang": "English",
  "lang_code": "en",
  "pos": "name",
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        {
          "kind": "topical",
          "langcode": "en",
          "name": "Cycling",
          "orig": "en:Cycling",
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            "Transport",
            "All topics",
            "Fundamental"
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      ],
      "glosses": [
        "A direct action event in which bicycle riders travel through city streets as a group."
      ],
      "id": "en-Critical_Mass-en-name-a76SFEAD",
      "links": [
        [
          "direct action",
          "direct action"
        ],
        [
          "bicycle",
          "bicycle"
        ]
      ]
    }
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  "word": "Critical Mass"
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      "expansion": "Critical Mass",
      "name": "en-proper noun"
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  "lang": "English",
  "lang_code": "en",
  "pos": "name",
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        "en:Cycling"
      ],
      "glosses": [
        "A direct action event in which bicycle riders travel through city streets as a group."
      ],
      "links": [
        [
          "direct action",
          "direct action"
        ],
        [
          "bicycle",
          "bicycle"
        ]
      ]
    }
  ],
  "word": "Critical Mass"
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