"一斉に" meaning in Japanese

{
  "forms": [
    {
      "form": "一斉に",
      "ruby": [
        [
          "一",
          "いっ"
        ],
        [
          "斉",
          "せい"
        ]
      ],
      "tags": [
        "canonical"
      ]
    },
    {
      "form": "issei ni",
      "tags": [
        "romanization"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "adverb",
        "2": "いっせい に"
      },
      "expansion": "一(いっ)斉(せい)に • (issei ni)",
      "name": "ja-pos"
    }
  ],
  "lang": "Japanese",
  "lang_code": "ja",
  "pos": "adv",
  "senses": [
    {
      "categories": [
        {
          "_dis": "47 53",
          "kind": "other",
          "name": "Japanese terms with 2 kanji",
          "parents": [],
          "source": "w+disamb"
        }
      ],
      "glosses": [
        "all together"
      ],
      "id": "en-一斉に-ja-adv-uhr0jupN"
    },
    {
      "categories": [
        {
          "_dis": "32 68",
          "kind": "other",
          "name": "Japanese entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w+disamb"
        },
        {
          "_dis": "8 92",
          "kind": "other",
          "name": "Japanese links with redundant wikilinks",
          "parents": [
            "Links with redundant wikilinks",
            "Entry maintenance"
          ],
          "source": "w+disamb"
        },
        {
          "_dis": "47 53",
          "kind": "other",
          "name": "Japanese terms with 2 kanji",
          "parents": [],
          "source": "w+disamb"
        },
        {
          "_dis": "23 77",
          "kind": "other",
          "name": "Japanese terms with multiple readings",
          "parents": [],
          "source": "w+disamb"
        },
        {
          "_dis": "29 71",
          "kind": "other",
          "name": "Japanese terms with non-redundant non-automated sortkeys",
          "parents": [
            "Terms with non-redundant non-automated sortkeys",
            "Entry maintenance"
          ],
          "source": "w+disamb"
        },
        {
          "_dis": "8 92",
          "kind": "other",
          "name": "Japanese terms with redundant sortkeys",
          "parents": [
            "Terms with redundant sortkeys",
            "Entry maintenance"
          ],
          "source": "w+disamb"
        },
        {
          "_dis": "17 83",
          "kind": "other",
          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w+disamb"
        },
        {
          "_dis": "10 90",
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w+disamb"
        },
        {
          "_dis": "0 100",
          "kind": "topical",
          "langcode": "ja",
          "name": "Time",
          "orig": "ja:Time",
          "parents": [
            "All topics",
            "Fundamental"
          ],
          "source": "w+disamb"
        }
      ],
      "glosses": [
        "all at once, simultaneously"
      ],
      "id": "en-一斉に-ja-adv-SVEV-Sfy",
      "links": [
        [
          "simultaneously",
          "simultaneously"
        ]
      ]
    }
  ],
  "word": "一斉に"
}

{
  "categories": [
    "Japanese adverbs",
    "Japanese entries with incorrect language header",
    "Japanese lemmas",
    "Japanese links with redundant wikilinks",
    "Japanese terms spelled with first grade kanji",
    "Japanese terms spelled with secondary school kanji",
    "Japanese terms with 2 kanji",
    "Japanese terms with multiple readings",
    "Japanese terms with non-redundant non-automated sortkeys",
    "Japanese terms with redundant sortkeys",
    "Pages with 1 entry",
    "Pages with entries",
    "ja:Time"
  ],
  "forms": [
    {
      "form": "一斉に",
      "ruby": [
        [
          "一",
          "いっ"
        ],
        [
          "斉",
          "せい"
        ]
      ],
      "tags": [
        "canonical"
      ]
    },
    {
      "form": "issei ni",
      "tags": [
        "romanization"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "adverb",
        "2": "いっせい に"
      },
      "expansion": "一(いっ)斉(せい)に • (issei ni)",
      "name": "ja-pos"
    }
  ],
  "lang": "Japanese",
  "lang_code": "ja",
  "pos": "adv",
  "senses": [
    {
      "glosses": [
        "all together"
      ]
    },
    {
      "glosses": [
        "all at once, simultaneously"
      ],
      "links": [
        [
          "simultaneously",
          "simultaneously"
        ]
      ]
    }
  ],
  "word": "一斉に"
}

{
  "called_from": "parser/1336",
  "msg": "no corresponding start tag found for </span>",
  "path": [
    "一斉に"
  ],
  "section": "Japanese",
  "subsection": "adverb",
  "title": "一斉に",
  "trace": ""
}