inefficacious

inefficacious — adjective

  • inefficaciouspositive
  • more inefficaciouscomparative
  • most inefficacioussuperlative

1. describes an action, method, or treatment that does not achieve the result it wa

1.形容詞C1
釋義

describes an action, method, or treatment that does not achieve the result it was meant to achieve, often because it is not strong or suitable enough

例句

Jiwoo's doctor decided that the first medicine was inefficacious and switched to a stronger treatment.

was inefficacious — predicative use with a linking verb

The new teaching method proved inefficacious; students still struggled with basic reading skills.

proved inefficacious — common formal pattern

同義詞
  • ineffective

    much more common and less formal; the everyday alternative to inefficacious

  • futile

    suggests hopelessness and that effort is wasted; stronger emotional tone than inefficacious

  • unproductive

    focuses on the lack of results rather than a lack of power; common in workplace contexts

反義詞
  • efficacious

    the direct formal antonym; equally rare and formal

  • effective

    the most common antonym across all registers

  • productive

    focuses on achieving good results; common in workplace and everyday contexts

文法句型

be inefficacious

prove inefficacious

remain inefficacious

deem someone/something inefficacious

用法筆記

This is a very formal word, most common in medical, legal, and academic writing. In everyday conversation, speakers typically use 'ineffective' or 'useless' instead. Frequently appears after linking verbs such as 'prove', 'remain', and 'be deemed'.

常見錯誤

❌I tried to fix my bike but my tools were inefficacious.
✅I tried to fix my bike but my tools were useless.
💡'inefficacious' is too formal for everyday minor problems; use 'ineffective' or 'useless' instead.
❌The drug was inefficacious for him.
✅The drug was inefficacious in his case.
💡while 'for' is sometimes seen, 'in' is the more natural preposition when referring to a person's specific situation.