noun Etymology: Late Latin inefficacia, from Latin inefficac-, inefficax inefficacious, from in- + efficac-, efficax efficacious Date: circa 1615 lack of power to produce a desired effect
INEFFICACY
Meaning of INEFFICACY in English
Merriam Webster. Explanatory English dictionary Merriam Webster. Толковый словарь английского языка Мерриам-Уэбстер. 2012