- Word Combinations (adjective)
|part of speech:
||causing or capable of causing a desired result; effectual; effective.
The treatment showed signs of being efficacious for this group of patients.
- ineffective, inefficacious
- similar words:
- effective, efficient, fruitful, valid
||active, capable, potent, productive, successful, telling
||efficaciously (adv.), efficaciousness (n.)