Efficacious
Drug labels, bug sprays, and study methods all make the same promise with different fine print; this adjective is reserved for the ones that actually deliver.
Learn This WordMeaning
Successfully producing the intended result; effective in action.
Memory trick
EFFICACIOUS carries "efficacy" inside it: efficacy = power to produce results.
Examples
The new protocol proved more efficacious than two years of ad hoc fixes.
Gargling salt water is a cheap, efficacious remedy for a sore throat.
Door knocking is still the most efficacious tactic in local races.
Synonyms
Antonyms
Etymology
From Latin efficax "powerful, effective," from ex- "out" + facere "to do, make."
Usage Notes
Formal cousin of "effective," common in medicine, law, and policy. It describes results, not effort.
Real-life contexts
Discuss medicine: "The trial found the dose safe and efficacious."
Discuss process: "One efficacious meeting beats five status calls."
Discuss habits: "The simplest efficacious routine is the one you keep."
Common Mistakes
Reserve it for things proven to work. A plan you merely hope will work is promising, not efficacious.
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Start LearningQuick Facts
Part of Speech
adjective
Difficulty
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