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Synonyms

inefficacious

American  
[in-ef-i-key-shuhs] / ˌɪn ɛf ɪˈkeɪ ʃəs /

adjective

  1. not able to produce the desired effect; ineffective.


inefficacious British  
/ ˌɪnɛfɪˈkæsɪtɪ, ˌɪnɛfɪˈkeɪʃəs, ɪnˈɛfɪkəsɪ /

adjective

  1. failing to produce the desired effect

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

Etymology

Origin of inefficacious

First recorded in 1650–60; in- 3 + efficacious

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

Most nostrums hit at only one of the causes and so are frequently inefficacious.

From Time Magazine Archive

Remedies for the starling plague were suggested, some facetious, some earnest, all equally inefficacious.

From Time Magazine Archive

As far as producing the effect contemplated was concerned, the law was altogether inefficacious.

From The Rise of Canada, from Barbarism to Wealth and Civilisation Volume 1 by Charles Roger

They were as unfriendly to the old confederation as to the system now proposed, but bore it with more patience because it was wholly inefficacious.

From Essays on the Constitution of the United States by Paul Leicester Ford

It is, at least, quite certain that other means will prove inefficacious, if this be not superadded.

From Three Prize Essays on American Slavery by A.C. Baldwin

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