"demon core" meaning in English

{
  "etymology_text": "So called because of its involvement in two fatal criticality accidents at the Los Alamos Laboratory in 1945 and 1946.",
  "forms": [
    {
      "form": "the demon core",
      "tags": [
        "canonical"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "def": "1"
      },
      "expansion": "the demon core",
      "name": "en-prop"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "name",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "A spherical subcritical mass of plutonium manufactured during World War II by the United States as a fissile core for an early atomic bomb."
      ],
      "id": "en-demon_core-en-name-a4QT~66Z",
      "links": [
        [
          "spherical",
          "spherical"
        ],
        [
          "subcritical",
          "subcritical"
        ],
        [
          "mass",
          "mass"
        ],
        [
          "plutonium",
          "plutonium"
        ],
        [
          "World War II",
          "World War II"
        ],
        [
          "United States",
          "United States"
        ],
        [
          "fissile",
          "fissile"
        ],
        [
          "core",
          "core"
        ],
        [
          "atomic bomb",
          "atomic bomb"
        ]
      ],
      "raw_glosses": [
        "(historical) A spherical subcritical mass of plutonium manufactured during World War II by the United States as a fissile core for an early atomic bomb."
      ],
      "tags": [
        "historical"
      ],
      "translations": [
        {
          "code": "id",
          "lang": "Indonesian",
          "sense": "spherical mass of plutonium",
          "word": "Inti iblis"
        },
        {
          "code": "ja",
          "lang": "Japanese",
          "roman": "Dīmon Koa",
          "sense": "spherical mass of plutonium",
          "word": "デーモン・コア"
        },
        {
          "code": "pl",
          "lang": "Polish",
          "sense": "spherical mass of plutonium",
          "word": "Diabelski rdzeń"
        },
        {
          "code": "vi",
          "lang": "Vietnamese",
          "sense": "spherical mass of plutonium",
          "word": "Lõi Quỷ"
        }
      ],
      "wikipedia": [
        "demon core"
      ]
    }
  ],
  "word": "demon core"
}

{
  "etymology_text": "So called because of its involvement in two fatal criticality accidents at the Los Alamos Laboratory in 1945 and 1946.",
  "forms": [
    {
      "form": "the demon core",
      "tags": [
        "canonical"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "def": "1"
      },
      "expansion": "the demon core",
      "name": "en-prop"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "name",
  "senses": [
    {
      "categories": [
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English proper nouns",
        "English terms with historical senses",
        "English uncountable nouns"
      ],
      "glosses": [
        "A spherical subcritical mass of plutonium manufactured during World War II by the United States as a fissile core for an early atomic bomb."
      ],
      "links": [
        [
          "spherical",
          "spherical"
        ],
        [
          "subcritical",
          "subcritical"
        ],
        [
          "mass",
          "mass"
        ],
        [
          "plutonium",
          "plutonium"
        ],
        [
          "World War II",
          "World War II"
        ],
        [
          "United States",
          "United States"
        ],
        [
          "fissile",
          "fissile"
        ],
        [
          "core",
          "core"
        ],
        [
          "atomic bomb",
          "atomic bomb"
        ]
      ],
      "raw_glosses": [
        "(historical) A spherical subcritical mass of plutonium manufactured during World War II by the United States as a fissile core for an early atomic bomb."
      ],
      "tags": [
        "historical"
      ],
      "wikipedia": [
        "demon core"
      ]
    }
  ],
  "translations": [
    {
      "code": "id",
      "lang": "Indonesian",
      "sense": "spherical mass of plutonium",
      "word": "Inti iblis"
    },
    {
      "code": "ja",
      "lang": "Japanese",
      "roman": "Dīmon Koa",
      "sense": "spherical mass of plutonium",
      "word": "デーモン・コア"
    },
    {
      "code": "pl",
      "lang": "Polish",
      "sense": "spherical mass of plutonium",
      "word": "Diabelski rdzeń"
    },
    {
      "code": "vi",
      "lang": "Vietnamese",
      "sense": "spherical mass of plutonium",
      "word": "Lõi Quỷ"
    }
  ],
  "word": "demon core"
}