"puffing Billy" meaning in English

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      "expansion": "puffing Billy",
      "name": "en-noun"
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
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          "kind": "other",
          "name": "English entries with incorrect language header",
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      "examples": [
        {
          "ref": "1969, Allen V. Ross, Vice in Bombay, London: Tallis Press, page 148:",
          "text": "The temple, halfway up the Matheran hills, was approached by a 'puffing billy' train on a zigzag railway from Neral, two miles from Bombay.",
          "type": "quote"
        }
      ],
      "glosses": [
        "A steam locomotive engine."
      ],
      "id": "en-puffing_Billy-en-noun-2SqR2WlB",
      "links": [
        [
          "steam",
          "steam"
        ],
        [
          "locomotive",
          "locomotive"
        ],
        [
          "engine",
          "engine"
        ]
      ],
      "raw_glosses": [
        "(slang, obsolete) A steam locomotive engine."
      ],
      "tags": [
        "obsolete",
        "slang"
      ]
    }
  ],
  "word": "puffing Billy"
}

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      "expansion": "puffing Billy",
      "name": "en-noun"
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "English nouns with unknown or uncertain plurals",
        "English slang",
        "English terms with obsolete senses",
        "English terms with quotations",
        "Pages with 1 entry",
        "Pages with entries"
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      "examples": [
        {
          "ref": "1969, Allen V. Ross, Vice in Bombay, London: Tallis Press, page 148:",
          "text": "The temple, halfway up the Matheran hills, was approached by a 'puffing billy' train on a zigzag railway from Neral, two miles from Bombay.",
          "type": "quote"
        }
      ],
      "glosses": [
        "A steam locomotive engine."
      ],
      "links": [
        [
          "steam",
          "steam"
        ],
        [
          "locomotive",
          "locomotive"
        ],
        [
          "engine",
          "engine"
        ]
      ],
      "raw_glosses": [
        "(slang, obsolete) A steam locomotive engine."
      ],
      "tags": [
        "obsolete",
        "slang"
      ]
    }
  ],
  "word": "puffing Billy"
}