[1] : The Collaborative International Dictionary of English v.0.48

inefficacy \inef"ficacy\, n. l. inefficacia. see in- not,
   and efficacy.
   lack of power to produce the desired or proper effect;
   inefficiency; ineffectualness; futility; uselessness;
   fruitlessness; as, the inefficacy of medicines or means.
   1913 webster

         the seeming inefficacy of censures.      --bp. hall.
   1913 webster

         the inefficacy was soon proved, like that of many
         similar medicines.                       --james
                                                  gregory.
   1913 webster
see also:
in- efficacy 

[2] : WordNet (r) 2.0

inefficacy
     n : a lack of efficacy syn: inefficaciousness ant: efficacy
see also:
inefficaciousness efficacy 

Inefficacy >> I Words
Inefficacy, definition of term: Inefficacy
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