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inefficacious
[ in-ef-i-key-shuhs ]
/ ˌɪn ɛf ɪˈkeɪ ʃəs /
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This shows grade level based on the word's complexity.
adjective
not able to produce the desired effect; ineffective.
QUIZ
QUIZ YOURSELF ON "WAS" VS. "WERE"!
Were you ready for a quiz on this topic? Well, here it is! See how well you can differentiate between the uses of "was" vs. "were" in this quiz.
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“Was” is used for the indicative past tense of “to be,” and “were” is only used for the subjunctive past tense.
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/, nounWords 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
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), nounCollins English Dictionary - Complete & Unabridged 2012 Digital Edition
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