adjective
- not producing the desired effect; ineffective
Usage: formal
Examples
- The new policy proved inefficacious in reducing crime rates.
- Despite multiple attempts, the treatment remained inefficacious.
- The committee’s inefficacious efforts disappointed the community.
- His inefficacious leadership led to the project’s failure.
- The medicine was deemed inefficacious after clinical trials.
- Their inefficacious strategy cost them the election.