# preposterous

/pɹɪˈpɑstɝəs/ (US) · /pɹɪpˈɒstəɹəs/ (UK) · CEFR C1 · Adjective

Source: https://englishreference.com/word/preposterous
Updated: 2026-05-08

## Definition

completely silly or impossible to believe. You use this when an idea or situation is so strange that it makes no sense at all.

For teachers: contrary to reason or common sense; utterly absurd or ridiculous. Often used to express strong disbelief or indignation regarding a proposal or claim.

## Examples

- The idea that the moon is made of cheese is preposterous.
- It is preposterous to suggest that a professional athlete could survive on a diet of only candy.
- The defense attorney argued that the prosecution's timeline was preposterous, as it required the defendant to be in two cities simultaneously without any means of rapid transport.

## Usage notes

- Often used predicatively after linking verbs like 'be', 'sound', or 'seem'.

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