"downtube" meaning in English

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        "2": "down",
        "3": "tube"
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      "expansion": "down + tube",
      "name": "compound"
    }
  ],
  "etymology_text": "down + tube",
  "forms": [
    {
      "form": "downtubes",
      "tags": [
        "plural"
      ]
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      "expansion": "downtube (plural downtubes)",
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  "lang_code": "en",
  "pos": "noun",
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      "alt_of": [
        {
          "word": "down tube"
        }
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        {
          "kind": "topical",
          "langcode": "en",
          "name": "Bicycle parts",
          "orig": "en:Bicycle parts",
          "parents": [
            "Cycling",
            "Transport",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "Alternative form of down tube"
      ],
      "id": "en-downtube-en-noun-x9~5nldH",
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          "down tube#English"
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  "word": "downtube"
}

{
  "etymology_templates": [
    {
      "args": {
        "1": "en",
        "2": "down",
        "3": "tube"
      },
      "expansion": "down + tube",
      "name": "compound"
    }
  ],
  "etymology_text": "down + tube",
  "forms": [
    {
      "form": "downtubes",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
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      "expansion": "downtube (plural downtubes)",
      "name": "en-noun"
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
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      "alt_of": [
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          "word": "down tube"
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  "word": "downtube"
}