[ˌɛfɪˈkeɪʃəs], (Adjective)

Definitions:
- (of something inanimate or abstract) successful in producing a desired or intended result; effective
(e.g: this treatment was efficacious in some cases)


Phrases:

Origin:
early 16th century: from Latin efficax, efficac- (from efficere ‘accomplish’: see effect)+ -ious