adj.
Pronunciation: ˌ e-f ə - ' k ā -sh ə s
Function: adjective
Etymology: Latin efficac-, efficax, from efficere
Date: 1528
: having the power to produce a desired effect <an efficacious remedy>
synonyms see EFFECTIVE
– ef · fi · ca · cious · ly adverb
– ef · fi · ca · cious · ness noun