inefficacious

[ in-ef-i-key-shuhs ]

See synonyms for: inefficacious inefficaciously on Thesaurus.com

adjective

not able to produce the desired effect; ineffective.

Origin of inefficacious

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

Other words from inefficacious

in·ef·fi·ca·cious·ly, adverb
in·ef·fi·ca·cious·ness, in·ef·fi·cac·i·ty [in-ef-i-kas-i-tee], /ˌɪn ɛf ɪˈkæs ɪ ti/, noun

Words Nearby inefficacious

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use inefficacious in a sentence

All attempts at cure proving inefficacious, he had at length to settle down once more in London.
Karl Marx | Achille Loria
The next was in 1641, when Charles I. returned from his imprudent and inefficacious journey into Scotland.
The Mirror of Literature, Amusement, and Instruction | Various
I therefore once more directed squill, with decoction of seneka and sal sodæ; but it was inefficacious.
An Account of the Foxglove and some of its Medical Uses | William Withering
The trials were made only on small animals, but in each case the alleged remedy proved inefficacious.
The Romance of Natural History, Second Series | Philip Henry Gosse
Their united efforts were vain, however; and even the remedies suggested by Apollo, god of medicine, proved inefficacious.
Myths of Greece and Rome | H. A. Guerber

British Dictionary definitions for inefficacious

inefficacious

/ (ˌɪnɛfɪˈkeɪʃəs) /

adjective

failing to produce the desired effect

Derived forms of inefficacious

inefficaciously, adverb
inefficacy (ɪnˈɛfɪkəsɪ), inefficaciousness or inefficacity (ˌɪnɛfɪˈkæsɪtɪ), noun

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

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