"parallel motion" meaning in English

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      "expansion": "parallel motion",
      "name": "en-noun"
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
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          "kind": "other",
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      ],
      "glosses": [
        "Any linkage by which circular motion may be changed into motion in a straight line."
      ],
      "id": "en-parallel_motion-en-noun-pei50TFi",
      "links": [
        [
          "engineering",
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        [
          "linkage",
          "linkage"
        ],
        [
          "circular",
          "circular"
        ]
      ],
      "raw_glosses": [
        "(engineering) Any linkage by which circular motion may be changed into motion in a straight line."
      ],
      "topics": [
        "engineering",
        "natural-sciences",
        "physical-sciences"
      ]
    }
  ],
  "word": "parallel motion"
}

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      "expansion": "parallel motion",
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
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        "en:Engineering"
      ],
      "glosses": [
        "Any linkage by which circular motion may be changed into motion in a straight line."
      ],
      "links": [
        [
          "engineering",
          "engineering#Noun"
        ],
        [
          "linkage",
          "linkage"
        ],
        [
          "circular",
          "circular"
        ]
      ],
      "raw_glosses": [
        "(engineering) Any linkage by which circular motion may be changed into motion in a straight line."
      ],
      "topics": [
        "engineering",
        "natural-sciences",
        "physical-sciences"
      ]
    }
  ],
  "word": "parallel motion"
}