in·ef·fi·ca·cy 
(ĭn-ĕfĭ-kə-sē)
(ĭn-ĕfĭ-kə-sē)n.
The state or quality of being incapable of producing a desired effect or result.
- histogenetic
- histogenetically
- histogenic
- histogenically
- histogram
- histologic
- histological
- histologically
- histologist
- histology
- histolysis
- histolytic
- histomoniasis
- histone
- histopathologic
- histopathological
- histopathologically
- histopathologist
- histopathology
- histophysiologic
- histophysiological
- histophysiology
- histoplasmosis
- historian
- historiated