"km²" meaning in All languages combined

{
  "head_templates": [
    {
      "args": {
        "1": "mul",
        "2": "symbol"
      },
      "expansion": "km²",
      "name": "head"
    }
  ],
  "lang": "Translingual",
  "lang_code": "mul",
  "pos": "symbol",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Translingual entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "square kilometers"
      ],
      "id": "en-km²-mul-symbol-Ki-kKJmn",
      "links": [
        [
          "square kilometer",
          "square kilometer"
        ]
      ]
    }
  ],
  "word": "km²"
}

{
  "head_templates": [
    {
      "args": {
        "1": "mul",
        "2": "symbol"
      },
      "expansion": "km²",
      "name": "head"
    }
  ],
  "lang": "Translingual",
  "lang_code": "mul",
  "pos": "symbol",
  "senses": [
    {
      "categories": [
        "Pages with 1 entry",
        "Translingual entries with incorrect language header",
        "Translingual lemmas",
        "Translingual symbols",
        "Translingual terms spelled with ²"
      ],
      "glosses": [
        "square kilometers"
      ],
      "links": [
        [
          "square kilometer",
          "square kilometer"
        ]
      ]
    }
  ],
  "word": "km²"
}