"top gear" meaning in English

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      "expansion": "top gear",
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
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      "examples": [
        {
          "ref": "2022 January 12, Benedict le Vay, “The heroes of Soham...”, in RAIL, number 948, page 42",
          "text": "The Second World War was reaching fever pitch, with the entire Allied effort in top gear for the imminent invasion of Europe, while later that month buzz bombs would start falling on London.",
          "type": "quotation"
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      ],
      "glosses": [
        "The highest gear that is available in a motor vehicle or car."
      ],
      "id": "en-top_gear-en-noun-lRsz4nsP"
    }
  ],
  "word": "top gear"
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      "args": {
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      "expansion": "top gear",
      "name": "en-noun"
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
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      "examples": [
        {
          "ref": "2022 January 12, Benedict le Vay, “The heroes of Soham...”, in RAIL, number 948, page 42",
          "text": "The Second World War was reaching fever pitch, with the entire Allied effort in top gear for the imminent invasion of Europe, while later that month buzz bombs would start falling on London.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "The highest gear that is available in a motor vehicle or car."
      ]
    }
  ],
  "word": "top gear"
}