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

inefficiency \in`effi"ciency\, n.
   the quality of being inefficient; lack of power or energy
   sufficient for the desired effect; inefficacy; incapacity;
   as, he was discharged from his position for inefficiency.
   1913 webster

[2] : WordNet (r) 2.0

inefficiency
     n : unskillfulness resulting from a lack of efficiency ant: efficiency
see also:
efficiency 

[3] : Moby Thesaurus II by Grady Ward, 1.0

45 moby thesaurus words for "inefficiency":
   disability, disablement, disqualification, imbecility, inability,
   inadeptness, inadequacy, inaptitude, inaptness, inattentiveness,
   incapability, incapacitation, incapacity, incompetence,
   incompetency, indexterity, ineffectiveness, ineffectuality,
   ineptitude, ineptness, infancy, inferiority, insufficiency,
   legal incapacity, maladjustment, maladroitness, mediocrity,
   minority, pedestrianism, rustiness, skill-lessness,
   thoughtlessness, unaptness, uncleverness, undeftness,
   undexterousness, undextrousness, unfitness, unfittedness,
   unintelligence, unproficiency, unschooledness, unskillfulness,
   untrainedness, wardship

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