# idiocy

/ˈɪdiəsi/ (US) · /ˈɪdɪˌɒsi/ (UK) · CEFR C1 · Noun

Source: https://englishreference.com/word/idiocy
Updated: 2026-05-19

## Definition

the quality of being very foolish or lacking common sense. It is a strong word that people use when they are very angry or frustrated with someone's behavior.

For teachers: the quality of being extremely foolish or lacking in intelligence. Often used in a pejorative sense to describe a person's behavior or a specific action.

## Examples

- His idiocy made the whole project a total failure.
- The manager was furious at the employee's idiocy, which had caused a major delay in the delivery.
- While the plan was technically sound, the idiocy of the team's execution rendered it completely ineffective in the eyes of the board.

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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.