First Known Use: 1528
Dictionary
efficacious
adjective ef·fi·ca·cious \ˌe-fə-ˈkā-shəs\
: having the power to produce a desired result or effect
Full Definition of EFFICACIOUS
: having the power to produce a desired effect <an efficacious remedy>
— ef·fi·ca·cious·ly adverb
— ef·fi·ca·cious·ness noun
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Origin of EFFICACIOUS
Latin efficac-, efficax, from efficere
Related to EFFICACIOUS
- Antonyms
- fruitless, ineffective, ineffectual, inefficient, inoperative, unfruitful, unproductive, useless
Synonym Discussion of EFFICACIOUS
effective, effectual, efficient, efficacious mean producing or capable of producing a result. effective stresses the actual production of or the power to produce an effect <an effective rebuttal>. effectual suggests the accomplishment of a desired result especially as viewed after the fact <the measures to stop the pilfering proved effectual>. efficient suggests an acting or a potential for action or use in such a way as to avoid loss or waste of energy in effecting, producing, or functioning <an efficient small car>. efficacious suggests possession of a special quality or virtue that gives effective power <a detergent that is efficacious in removing grease>.
Rhymes with EFFICACIOUS
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