"巻頭" meaning in Japanese

{
  "antonyms": [
    {
      "roman": "kanmatsu",
      "ruby": [
        [
          "巻末",
          "かんまつ"
        ]
      ],
      "word": "巻末"
    },
    {
      "roman": "kanbi",
      "ruby": [
        [
          "巻尾",
          "かんび"
        ]
      ],
      "word": "巻尾"
    }
  ],
  "forms": [
    {
      "form": "巻頭",
      "ruby": [
        [
          "巻",
          "かん"
        ],
        [
          "頭",
          "とう"
        ]
      ],
      "tags": [
        "canonical"
      ]
    },
    {
      "form": "kantō",
      "tags": [
        "romanization"
      ]
    },
    {
      "form": "kwantou",
      "tags": [
        "romanization"
      ]
    },
    {
      "form": "くわんとう",
      "roman": "kwantou",
      "tags": [
        "hiragana",
        "historical"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "かんとう",
        "hhira": "くわんとう"
      },
      "expansion": "巻(かん)頭(とう) • (kantō) ^(←くわんとう (kwantou)?)",
      "name": "ja-noun"
    }
  ],
  "lang": "Japanese",
  "lang_code": "ja",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "Japanese entries with incorrect language header",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Japanese links with redundant alt parameters",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Japanese links with redundant wikilinks",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Japanese terms with 2 kanji",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Japanese terms with Heiban pitch accent (Tōkyō)",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Japanese terms with redundant sortkeys",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "langcode": "ja",
          "name": "Books",
          "orig": "ja:Books",
          "parents": [],
          "source": "w"
        }
      ],
      "glosses": [
        "beginning / opening of a book"
      ],
      "id": "en-巻頭-ja-noun-4iJMR5-0",
      "links": [
        [
          "beginning",
          "beginning"
        ],
        [
          "opening",
          "opening"
        ],
        [
          "book",
          "book"
        ]
      ],
      "synonyms": [
        {
          "roman": "kanshu",
          "ruby": [
            [
              "巻首",
              "かんしゅ"
            ]
          ],
          "word": "巻首"
        }
      ]
    }
  ],
  "sounds": [
    {
      "other": "かんとー"
    },
    {
      "ipa": "[kã̠nto̞ː]"
    }
  ],
  "word": "巻頭"
}

{
  "antonyms": [
    {
      "roman": "kanmatsu",
      "ruby": [
        [
          "巻末",
          "かんまつ"
        ]
      ],
      "word": "巻末"
    },
    {
      "roman": "kanbi",
      "ruby": [
        [
          "巻尾",
          "かんび"
        ]
      ],
      "word": "巻尾"
    }
  ],
  "forms": [
    {
      "form": "巻頭",
      "ruby": [
        [
          "巻",
          "かん"
        ],
        [
          "頭",
          "とう"
        ]
      ],
      "tags": [
        "canonical"
      ]
    },
    {
      "form": "kantō",
      "tags": [
        "romanization"
      ]
    },
    {
      "form": "kwantou",
      "tags": [
        "romanization"
      ]
    },
    {
      "form": "くわんとう",
      "roman": "kwantou",
      "tags": [
        "hiragana",
        "historical"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "かんとう",
        "hhira": "くわんとう"
      },
      "expansion": "巻(かん)頭(とう) • (kantō) ^(←くわんとう (kwantou)?)",
      "name": "ja-noun"
    }
  ],
  "lang": "Japanese",
  "lang_code": "ja",
  "pos": "noun",
  "senses": [
    {
      "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 わ",
        "Japanese terms spelled with second grade kanji",
        "Japanese terms spelled with sixth grade kanji",
        "Japanese terms with 2 kanji",
        "Japanese terms with Heiban pitch accent (Tōkyō)",
        "Japanese terms with IPA pronunciation",
        "Japanese terms with redundant sortkeys",
        "Pages with 1 entry",
        "Pages with entries",
        "ja:Books"
      ],
      "glosses": [
        "beginning / opening of a book"
      ],
      "links": [
        [
          "beginning",
          "beginning"
        ],
        [
          "opening",
          "opening"
        ],
        [
          "book",
          "book"
        ]
      ]
    }
  ],
  "sounds": [
    {
      "other": "かんとー"
    },
    {
      "ipa": "[kã̠nto̞ː]"
    }
  ],
  "synonyms": [
    {
      "roman": "kanshu",
      "ruby": [
        [
          "巻首",
          "かんしゅ"
        ]
      ],
      "word": "巻首"
    }
  ],
  "word": "巻頭"
}

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

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