Definition of inefficacy
: lack of power to produce a desired effect
Recent Examples of inefficacy from the Web
The giraffe, said Mivart, was a perfect example of natural selection’s inefficacy.
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Origin and Etymology of inefficacy
Late Latin inefficacia, from Latin inefficac-, inefficax inefficacious, from in- + efficac-, efficax efficacious
First Known Use: circa 1615
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