"slave cylinder" meaning in English

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      "form": "slave cylinders",
      "tags": [
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      "expansion": "slave cylinder (plural slave cylinders)",
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
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      "glosses": [
        "A small cylinder, dependent on a master cylinder, that contains a piston."
      ],
      "id": "en-slave_cylinder-en-noun-QyuC6BJr",
      "links": [
        [
          "engineering",
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        [
          "master cylinder",
          "master cylinder#English"
        ],
        [
          "piston",
          "piston#English"
        ]
      ],
      "raw_glosses": [
        "(engineering) A small cylinder, dependent on a master cylinder, that contains a piston."
      ],
      "topics": [
        "engineering",
        "natural-sciences",
        "physical-sciences"
      ]
    }
  ],
  "word": "slave cylinder"
}

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    {
      "form": "slave cylinders",
      "tags": [
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    }
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  "lang_code": "en",
  "pos": "noun",
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      "glosses": [
        "A small cylinder, dependent on a master cylinder, that contains a piston."
      ],
      "links": [
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        [
          "master cylinder",
          "master cylinder#English"
        ],
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          "piston#English"
        ]
      ],
      "raw_glosses": [
        "(engineering) A small cylinder, dependent on a master cylinder, that contains a piston."
      ],
      "topics": [
        "engineering",
        "natural-sciences",
        "physical-sciences"
      ]
    }
  ],
  "word": "slave cylinder"
}