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Synonyms

inefficacious

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

adjective

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


inefficacious British  
/ ˌɪnɛfɪˈkeɪʃəs /

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

Failing in its usual effect, the medicine was no longer continued; but every thing that was tried proved equally inefficacious, and he did not long survive.

From An Account of the Foxglove and some of its Medical Uses With Practical Remarks on Dropsy and Other Diseases by William Withering

The special field of private ethics is among the cases where punishment is "unprofitable" or "inefficacious," notably those which are the concern of prudence.

From The World's Greatest Books — Volume 14 — Philosophy and Economics by Sir John Alexander Hammerton

It was inefficacious, however, when one of these was involved in sin.

From A History of The Inquisition of The Middle Ages; volume I by Henry Charles Lea

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