"主軸" meaning in Japanese

{
  "forms": [
    {
      "form": "主軸",
      "ruby": [
        [
          "主",
          "しゅ"
        ],
        [
          "軸",
          "じく"
        ]
      ],
      "tags": [
        "canonical"
      ]
    },
    {
      "form": "shujiku",
      "tags": [
        "romanization"
      ]
    },
    {
      "form": "syudiku",
      "tags": [
        "romanization"
      ]
    },
    {
      "form": "しゅぢく",
      "roman": "syudiku",
      "tags": [
        "hiragana",
        "historical"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "しゅじく",
        "hhira": "しゅぢく"
      },
      "expansion": "主(しゅ)軸(じく) • (shujiku) ^(←しゅぢく (syudiku)?)",
      "name": "ja-noun"
    }
  ],
  "lang": "Japanese",
  "lang_code": "ja",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "_dis": "93 7",
          "kind": "other",
          "name": "Japanese entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w+disamb"
        },
        {
          "_dis": "96 4",
          "kind": "other",
          "name": "Japanese links with redundant alt parameters",
          "parents": [
            "Links with redundant alt parameters",
            "Entry maintenance"
          ],
          "source": "w+disamb"
        },
        {
          "_dis": "96 4",
          "kind": "other",
          "name": "Japanese links with redundant wikilinks",
          "parents": [
            "Links with redundant wikilinks",
            "Entry maintenance"
          ],
          "source": "w+disamb"
        },
        {
          "_dis": "96 4",
          "kind": "other",
          "name": "Japanese terms with redundant sortkeys",
          "parents": [
            "Terms with redundant sortkeys",
            "Entry maintenance"
          ],
          "source": "w+disamb"
        }
      ],
      "glosses": [
        "main shaft"
      ],
      "id": "en-主軸-ja-noun-F4zv7BHu",
      "links": [
        [
          "main",
          "main"
        ],
        [
          "shaft",
          "shaft"
        ]
      ]
    },
    {
      "glosses": [
        "principal axis"
      ],
      "id": "en-主軸-ja-noun-JBcK8CU8",
      "links": [
        [
          "principal",
          "principal"
        ],
        [
          "axis",
          "axis"
        ]
      ]
    }
  ],
  "sounds": [
    {
      "other": "しゅじく"
    },
    {
      "ipa": "[ɕɨᵝʑikɯ̟ᵝ]"
    }
  ],
  "wikipedia": [
    "ja:主軸"
  ],
  "word": "主軸"
}

{
  "categories": [
    "Japanese entries with incorrect language header",
    "Japanese lemmas",
    "Japanese links with redundant alt parameters",
    "Japanese links with redundant wikilinks",
    "Japanese nouns",
    "Japanese terms historically spelled with ぢ",
    "Japanese terms spelled with secondary school kanji",
    "Japanese terms spelled with third grade kanji",
    "Japanese terms with IPA pronunciation",
    "Japanese terms with redundant sortkeys",
    "Japanese terms written with two Han script characters"
  ],
  "forms": [
    {
      "form": "主軸",
      "ruby": [
        [
          "主",
          "しゅ"
        ],
        [
          "軸",
          "じく"
        ]
      ],
      "tags": [
        "canonical"
      ]
    },
    {
      "form": "shujiku",
      "tags": [
        "romanization"
      ]
    },
    {
      "form": "syudiku",
      "tags": [
        "romanization"
      ]
    },
    {
      "form": "しゅぢく",
      "roman": "syudiku",
      "tags": [
        "hiragana",
        "historical"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "しゅじく",
        "hhira": "しゅぢく"
      },
      "expansion": "主(しゅ)軸(じく) • (shujiku) ^(←しゅぢく (syudiku)?)",
      "name": "ja-noun"
    }
  ],
  "lang": "Japanese",
  "lang_code": "ja",
  "pos": "noun",
  "senses": [
    {
      "glosses": [
        "main shaft"
      ],
      "links": [
        [
          "main",
          "main"
        ],
        [
          "shaft",
          "shaft"
        ]
      ]
    },
    {
      "glosses": [
        "principal axis"
      ],
      "links": [
        [
          "principal",
          "principal"
        ],
        [
          "axis",
          "axis"
        ]
      ]
    }
  ],
  "sounds": [
    {
      "other": "しゅじく"
    },
    {
      "ipa": "[ɕɨᵝʑikɯ̟ᵝ]"
    }
  ],
  "wikipedia": [
    "ja:主軸"
  ],
  "word": "主軸"
}

{
  "called_from": "parser/304",
  "msg": "HTML tag <span> not properly closed",
  "path": [
    "主軸"
  ],
  "section": "Japanese",
  "subsection": "noun",
  "title": "主軸",
  "trace": "started on line 2, detected on line 2"
}

{
  "called_from": "parser/1336",
  "msg": "no corresponding start tag found for </span>",
  "path": [
    "主軸"
  ],
  "section": "Japanese",
  "subsection": "noun",
  "title": "主軸",
  "trace": ""
}