"untwinned" meaning in English

{
  "etymology_templates": [
    {
      "args": {
        "1": "en",
        "2": "un",
        "3": "twinned"
      },
      "expansion": "un- + twinned",
      "name": "prefix"
    }
  ],
  "etymology_text": "un- + twinned",
  "head_templates": [
    {
      "args": {
        "1": "-"
      },
      "expansion": "untwinned (not comparable)",
      "name": "en-adj"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "adj",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English terms prefixed with un-",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Mineralogy",
          "orig": "en:Mineralogy",
          "parents": [
            "Geology",
            "Earth sciences",
            "Sciences",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "Not having undergone twinning."
      ],
      "id": "en-untwinned-en-adj-opqYiBAj",
      "links": [
        [
          "mineralogy",
          "mineralogy"
        ],
        [
          "twinning",
          "twinning"
        ]
      ],
      "raw_glosses": [
        "(mineralogy) Not having undergone twinning."
      ],
      "tags": [
        "not-comparable"
      ],
      "topics": [
        "chemistry",
        "geography",
        "geology",
        "mineralogy",
        "natural-sciences",
        "physical-sciences"
      ]
    }
  ],
  "word": "untwinned"
}

{
  "etymology_templates": [
    {
      "args": {
        "1": "en",
        "2": "un",
        "3": "twinned"
      },
      "expansion": "un- + twinned",
      "name": "prefix"
    }
  ],
  "etymology_text": "un- + twinned",
  "head_templates": [
    {
      "args": {
        "1": "-"
      },
      "expansion": "untwinned (not comparable)",
      "name": "en-adj"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "adj",
  "senses": [
    {
      "categories": [
        "English adjectives",
        "English entries with incorrect language header",
        "English lemmas",
        "English terms prefixed with un-",
        "English uncomparable adjectives",
        "en:Mineralogy"
      ],
      "glosses": [
        "Not having undergone twinning."
      ],
      "links": [
        [
          "mineralogy",
          "mineralogy"
        ],
        [
          "twinning",
          "twinning"
        ]
      ],
      "raw_glosses": [
        "(mineralogy) Not having undergone twinning."
      ],
      "tags": [
        "not-comparable"
      ],
      "topics": [
        "chemistry",
        "geography",
        "geology",
        "mineralogy",
        "natural-sciences",
        "physical-sciences"
      ]
    }
  ],
  "word": "untwinned"
}