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inefficacious

[ in-ef-i-key-shuhs ]
/ ˌɪn ɛf ɪˈkeɪ ʃəs /
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See synonyms for: inefficacious / inefficaciously on Thesaurus.com
adjective
not able to produce the desired effect; ineffective.
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Origin of inefficacious

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

OTHER WORDS FROM inefficacious

in·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

Words nearby inefficacious

ineffable, ineffaceable, in effect, ineffective, ineffectual, inefficacious, inefficacy, inefficiency, inefficient, in effigy, inegalitarian
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022

Words related to inefficacious

abortive, anticlimactic, barren, bootless, defeasible, feckless, feeble, forceless, fruitless, futile, idle, impotent, inadequate, incompetent, indecisive, ineffective, inefficient, inept, inferior, innocuous

British Dictionary definitions for inefficacious

inefficacious
/ (ˌɪnɛfɪˈkeɪʃəs) /
adjective
failing to produce the desired effect

Derived forms of inefficacious

inefficaciously, 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
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