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Synonyms

inefficacy

American  
[in-ef-i-kuh-see] / ɪnˈɛf ɪ kə si /

noun

  1. lack of power or capacity to produce the desired effect.

Etymology

Origin of inefficacy

From the Late Latin word inefficācia, dating back to 1605–15. See in- 3, efficacy

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.