"Square-1" meaning in English

{
  "etymology_text": "A reference to the popular phrase \"back to square one\".",
  "head_templates": [
    {
      "args": {
        "1": "-"
      },
      "expansion": "Square-1 (uncountable)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Rubik's Cube",
          "orig": "en:Rubik's Cube",
          "parents": [
            "Games",
            "Toys",
            "Recreation",
            "Human activity",
            "Human behaviour",
            "Human",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "A puzzle similar to a Rubik's Cube that can change shape due to the way it is cut."
      ],
      "id": "en-Square-1-en-noun-Z4TrTU8J",
      "links": [
        [
          "puzzle",
          "puzzle"
        ],
        [
          "Rubik's Cube",
          "Rubik's Cube"
        ]
      ],
      "tags": [
        "uncountable"
      ],
      "wikipedia": [
        "Square-1 (puzzle)"
      ]
    }
  ],
  "word": "Square-1"
}

{
  "etymology_text": "A reference to the popular phrase \"back to square one\".",
  "head_templates": [
    {
      "args": {
        "1": "-"
      },
      "expansion": "Square-1 (uncountable)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "English terms spelled with numbers",
        "English uncountable nouns",
        "en:Rubik's Cube"
      ],
      "glosses": [
        "A puzzle similar to a Rubik's Cube that can change shape due to the way it is cut."
      ],
      "links": [
        [
          "puzzle",
          "puzzle"
        ],
        [
          "Rubik's Cube",
          "Rubik's Cube"
        ]
      ],
      "tags": [
        "uncountable"
      ],
      "wikipedia": [
        "Square-1 (puzzle)"
      ]
    }
  ],
  "word": "Square-1"
}