im·​be·​cil·​i·​ty ˌim-bə-ˈsi-lə-tē How to pronounce imbecility (audio)
plural imbecilities
: the quality or state of being very stupid or foolish : utter foolishness
… it seemed a very odd business, filled with illusions and delusions, at times noble to the point of imbecility and at other times base to the point of amorality.Colleen McCullough
also : futility
: something that is foolish or nonsensical
… his satire on the imbecilities and greed of politicians …Nicholas Von Hoffman
dated, now offensive; see usage paragraph below : the condition of being affected with moderate intellectual disability
Usage of Imbecility

The terms idiot, imbecile, moron, and their derivatives, such as imbecility, were formerly used as technical descriptors in medical, educational, and regulatory contexts. These uses were broadly rejected by the close of the 20th century and are now considered offensive.

Examples of imbecility in a Sentence

was arrested for the sheer imbecility of speeding down a dark road with no headlights on we were stunned by the imbecility of the ideas presented by this once-respected biologist

Word History


Middle English imbecillite "weakness of a body part, infirmity," borrowed from Middle French and Latin; Middle French imbecillité "weakness, feebleness, intellectual deficiency," borrowed from Latin imbēcillitāt-, imbēcillitās "physical or intellectual weakness," from imbēcillus "physically weak, feeble" + -itāt-, -itās -ity — more at imbecile entry 2

First Known Use

1624, in the meaning defined at sense 1a

Time Traveler
The first known use of imbecility was in 1624

Dictionary Entries Near imbecility

Cite this Entry

“Imbecility.” Dictionary, Merriam-Webster, Accessed 26 Feb. 2024.

Kids Definition


im·​be·​cil·​i·​ty ˌim-bə-ˈsil-ət-ē How to pronounce imbecility (audio)
plural imbecilities
: complete foolishness
: something very foolish

More from Merriam-Webster on imbecility

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