"pioneer axon" meaning in English

{
  "forms": [
    {
      "form": "pioneer axons",
      "tags": [
        "plural"
      ]
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  ],
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      "args": {},
      "expansion": "pioneer axon (plural pioneer axons)",
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
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          "langcode": "en",
          "name": "Neurology",
          "orig": "en:Neurology",
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            "Biology",
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      ],
      "glosses": [
        "An axon that lays down the initial growing path for the other axons of the same neuron to follow."
      ],
      "id": "en-pioneer_axon-en-noun--q1s1mon",
      "links": [
        [
          "neurology",
          "neurology"
        ],
        [
          "axon",
          "axon"
        ],
        [
          "neuron",
          "neuron"
        ]
      ],
      "raw_glosses": [
        "(neurology) An axon that lays down the initial growing path for the other axons of the same neuron to follow."
      ],
      "topics": [
        "medicine",
        "neurology",
        "neuroscience",
        "sciences"
      ],
      "wikipedia": [
        "pioneer axon"
      ]
    }
  ],
  "word": "pioneer axon"
}

{
  "forms": [
    {
      "form": "pioneer axons",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
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      "expansion": "pioneer axon (plural pioneer axons)",
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
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      "glosses": [
        "An axon that lays down the initial growing path for the other axons of the same neuron to follow."
      ],
      "links": [
        [
          "neurology",
          "neurology"
        ],
        [
          "axon",
          "axon"
        ],
        [
          "neuron",
          "neuron"
        ]
      ],
      "raw_glosses": [
        "(neurology) An axon that lays down the initial growing path for the other axons of the same neuron to follow."
      ],
      "topics": [
        "medicine",
        "neurology",
        "neuroscience",
        "sciences"
      ],
      "wikipedia": [
        "pioneer axon"
      ]
    }
  ],
  "word": "pioneer axon"
}