inefficacious

[in-ef-i-key-shuh s]

See more synonyms for inefficacious on Thesaurus.com

adjective

not able to produce the desired effect; ineffective.

Origin of inefficacious

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

Related formsin·ef·fi·ca·cious·ly, adverbin·ef·fi·ca·cious·ness, in·ef·fi·cac·i·ty

[in-ef-i-kas-i-tee] /ˌɪn ɛf ɪˈkæs ɪ ti/, noun

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Related Words for inefficacious

abortive, barren, bootless, feckless, feeble, fruitless, futile, idle, impotent, inadequate, incompetent, indecisive, ineffective, inefficient, inept, inferior, innocuous, inoperative, lame, limited

Examples from the Web for inefficacious

Historical Examples of inefficacious

Inefficacious they are not, unless they be too badly preached to obtain attention.
Ralph the Heir
Anthony Trollope
It was inefficacious, however, when one of these was involved in sin.
A History of The Inquisition of The Middle Ages; volume I
Henry Charles Lea
Is orthodoxy either so inefficacious or so moribund as you fancy?
The Grandchildren of the Ghetto
Israel Zangwill
But this plan of regulation was not only inefficacious, but unsafe.
The History of the Rise, Progress and Accomplishment of the
Thomas Clarkson
And what do you think he's goin' to do with them inefficacious knick- knacks?
Heart of the West
O. Henry

British Dictionary definitions for inefficacious

inefficacious

adjective

failing to produce the desired effect

Derived Formsinefficaciously, adverbinefficacy (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

Word Origin and History for inefficacious

adj.

1650s, from in- (1) "not, opposite of" + efficacious. Related: Inefficaciously; inefficaciousness (1640s).