# China syndrome

idiom

Source: https://englishreference.com/idiom/china-syndrome
Updated: 2026-08-10

## Meaning

A hypothetical kind of catastrophic failure in which a nuclear reactor melts through the floor of its containment system and (if on land) penetrates the Earth's surface, continuing downward as if (from a Western Hemispheric point of view) traveling through the planet toward China.

## Examples

- Engineers worry that a total cooling failure could lead to a China syndrome.
- Modern safety systems prevent a China syndrome from ever happening.
- The safety report warned that if the reactor core overheats, it could trigger a China syndrome, causing the molten material to melt through the containment floor.
- If the backup generators fail during a heatwave, the facility risks a China syndrome that would contaminate the groundwater deep below the plant.
- The movie plot centers on a whistleblower trying to warn the public about a potential China syndrome at a local power station.
- The catastrophic scenario of a China syndrome remains the ultimate nightmare for nuclear safety experts, representing the theoretical point where a meltdown penetrates the very foundation of the facility.

## Origin

China + syndrome. Popularized via the 1979 disaster thriller film The China Syndrome.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.