# diabolical

/ˌdaɪəˈbɑɫɪkəɫ/ (US) · /dˌaɪəbˈɒlɪkəl/ (UK) · CEFR C1 · Adjective

Source: https://englishreference.com/word/diabolical
Updated: 2026-05-18

## Definition

extremely evil, cruel, or difficult. You use this to describe something that is so bad it feels like it was made by the devil.

For teachers: extremely wicked, cruel, or evil; also used to describe something exceptionally difficult or unpleasant. Often used in a hyperbolic sense to express strong disapproval.

## Examples

- The diabolical plan failed because of a small mistake.
- The diabolical weather during the marathon made it impossible for the runners to finish the race.
- The novel features a diabolical antagonist whose schemes are so intricate that they seem to have been designed by a master of chaos rather than a human mind.

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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.