"motor unit" meaning in English

{
  "forms": [
    {
      "form": "motor units",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "motor unit (plural motor units)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Entries with translation boxes",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with 1 entry",
          "parents": [],
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        },
        {
          "kind": "other",
          "name": "Pages with entries",
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        },
        {
          "kind": "other",
          "name": "Terms with Finnish translations",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Terms with French translations",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Terms with Irish translations",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Terms with Swedish translations",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Neurology",
          "orig": "en:Neurology",
          "parents": [
            "Medicine",
            "Neuroscience",
            "Biology",
            "Healthcare",
            "Sciences",
            "Health",
            "All topics",
            "Body",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "A neuron with its associated muscle fibres."
      ],
      "id": "en-motor_unit-en-noun-yEtXLElq",
      "links": [
        [
          "neurology",
          "neurology"
        ],
        [
          "neuron",
          "neuron"
        ],
        [
          "muscle fibre",
          "muscle fibre"
        ]
      ],
      "raw_glosses": [
        "(neurology) A neuron with its associated muscle fibres."
      ],
      "topics": [
        "medicine",
        "neurology",
        "neuroscience",
        "sciences"
      ],
      "translations": [
        {
          "code": "fi",
          "lang": "Finnish",
          "sense": "neuron and fibres",
          "word": "motorinen yksikkö"
        },
        {
          "code": "fr",
          "lang": "French",
          "sense": "neuron and fibres",
          "tags": [
            "feminine"
          ],
          "word": "unité motrice"
        },
        {
          "code": "ga",
          "lang": "Irish",
          "sense": "neuron and fibres",
          "tags": [
            "masculine"
          ],
          "word": "aonad mótair"
        },
        {
          "code": "sv",
          "lang": "Swedish",
          "sense": "neuron and fibres",
          "word": "motorisk enhet"
        }
      ]
    }
  ],
  "word": "motor unit"
}

{
  "forms": [
    {
      "form": "motor units",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "motor unit (plural motor units)",
      "name": "en-noun"
    }
  ],
  "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",
        "Entries with translation boxes",
        "Pages with 1 entry",
        "Pages with entries",
        "Terms with Finnish translations",
        "Terms with French translations",
        "Terms with Irish translations",
        "Terms with Swedish translations",
        "en:Neurology"
      ],
      "glosses": [
        "A neuron with its associated muscle fibres."
      ],
      "links": [
        [
          "neurology",
          "neurology"
        ],
        [
          "neuron",
          "neuron"
        ],
        [
          "muscle fibre",
          "muscle fibre"
        ]
      ],
      "raw_glosses": [
        "(neurology) A neuron with its associated muscle fibres."
      ],
      "topics": [
        "medicine",
        "neurology",
        "neuroscience",
        "sciences"
      ]
    }
  ],
  "translations": [
    {
      "code": "fi",
      "lang": "Finnish",
      "sense": "neuron and fibres",
      "word": "motorinen yksikkö"
    },
    {
      "code": "fr",
      "lang": "French",
      "sense": "neuron and fibres",
      "tags": [
        "feminine"
      ],
      "word": "unité motrice"
    },
    {
      "code": "ga",
      "lang": "Irish",
      "sense": "neuron and fibres",
      "tags": [
        "masculine"
      ],
      "word": "aonad mótair"
    },
    {
      "code": "sv",
      "lang": "Swedish",
      "sense": "neuron and fibres",
      "word": "motorisk enhet"
    }
  ],
  "word": "motor unit"
}