"初頭" meaning in Japanese

{
  "forms": [
    {
      "form": "初頭",
      "ruby": [
        [
          "初",
          "しょ"
        ],
        [
          "頭",
          "とう"
        ]
      ],
      "tags": [
        "canonical"
      ]
    },
    {
      "form": "shotō",
      "tags": [
        "romanization"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "しょとう"
      },
      "expansion": "初(しょ)頭(とう) • (shotō)",
      "name": "ja-noun"
    }
  ],
  "lang": "Japanese",
  "lang_code": "ja",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "Japanese entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Japanese links with redundant wikilinks",
          "parents": [
            "Links with redundant wikilinks",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Japanese terms with redundant sortkeys",
          "parents": [
            "Terms with redundant sortkeys",
            "Entry maintenance"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "beginning of an age or a period, such as a century"
      ],
      "id": "en-初頭-ja-noun-fMTnk7Pc",
      "links": [
        [
          "beginning",
          "beginning"
        ]
      ]
    }
  ],
  "word": "初頭"
}

{
  "forms": [
    {
      "form": "初頭",
      "ruby": [
        [
          "初",
          "しょ"
        ],
        [
          "頭",
          "とう"
        ]
      ],
      "tags": [
        "canonical"
      ]
    },
    {
      "form": "shotō",
      "tags": [
        "romanization"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "しょとう"
      },
      "expansion": "初(しょ)頭(とう) • (shotō)",
      "name": "ja-noun"
    }
  ],
  "lang": "Japanese",
  "lang_code": "ja",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "Japanese entries with incorrect language header",
        "Japanese lemmas",
        "Japanese links with redundant wikilinks",
        "Japanese nouns",
        "Japanese terms spelled with fourth grade kanji",
        "Japanese terms spelled with second grade kanji",
        "Japanese terms with redundant sortkeys",
        "Japanese terms written with two Han script characters"
      ],
      "glosses": [
        "beginning of an age or a period, such as a century"
      ],
      "links": [
        [
          "beginning",
          "beginning"
        ]
      ]
    }
  ],
  "word": "初頭"
}

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