Meaning

2 senses
  1. (figuratively, uncountable)A essential instance or part of something, especially something malevolent.

  2. (figuratively, humorous, uncountable)Something that is especially dangerous and should not be tampered with, or otherwise reminiscent of the demon core.

Origin

Referred as such due to its involvement in two fatal criticality accidents at the Los Alam

Referred as such due to its involvement in two fatal criticality accidents at the Los Alamos Laboratory in 1945 and in 1946. In the late 2010s, the circumstances of the second incident were popularized widely by science history videos and internet memes.

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demon core — meaning, examples, forms, synonyms | Krumeto