Simple Definition of preposterous

from our Learner's Dictionary

preposterous

adjective

prɪˈpɑːstərəs

: very foolish or silly

a preposterous excuse

The whole idea is preposterous!

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“Preposterous.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/preposterous. Accessed 21 Jun. 2026.

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