Definition of preposterous
: contrary to nature, reason, or common sense : absurd
Examples of preposterous in a sentence
The whole idea is preposterous!
the idea that extraterrestrials built the pyramids is preposterous
Origin and Etymology of preposterous
Latin praeposterus, literally, in the wrong order, from prae- + posterus hinder, following — more at posterior
First Known Use: 1533
PREPOSTEROUS Defined for English Language Learners
Definition of preposterous for English Language Learners
: very foolish or silly
PREPOSTEROUS Defined for Kids
Seen and Heard
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