1. (a.) Not producing the effect intended or desired\; inefficacious; as, inefficient means or measures.

2. (a.) Incapable of, or indisposed to, effective action; habitually slack or remiss; effecting little or nothing; as, inefficient workmen; an inefficient administrator.

artless careless half-assed inadept inapt inattentive incapable incapable of incompetent ineffective ineffectual inefficacious inept inexpert inferior mediocre pedestrian poor skill-less slipshod slovenly thoughtless unable unable to unapt undeft undexterous undextrous unendowed unfacile unfit unfitted ungifted unintelligent unprepared unproficient unqualified unskilled unskillful untalented untrained unworkmanlike