inefficient

in- +‎ efficient

inefficient (comparative more inefficient, superlative most inefficient)

1. Not efficient; not producing the effect intended or desired; inefficacious

   Celery is an inefficient food.

2. Incapable of, or indisposed to, effective action; habitually slack or unproductive; effecting little or nothing
   • 1987, Ronald Reagan, Presidential Radio Address January 17, 1987

     The Defense Department, for example, has greatly expanded competitive bidding and is this year submitting to Congress the first-ever 2-year defense budget to replace the old, inefficient, year-by-year process.

   inefficient workers

   an inefficient administrator

   Jessica was terribly inefficient at cleaning, so her brother usually had to clean the whole room.

• efficient

inefficient (plural inefficients)

1. A person who cannot or does not work efficiently.
   • 1889, New York (State). Dept. of Labor. Bureau of Statistics, Annual Report (part 2, page 127)

     Two men were put to work who could not set their looms; a third man was taken on who helped the inefficients to set the looms. The other weavers thought this was a breach of their union rules and 18 of them struck […]

   • Jack London

     A general shaking up of the workers from top to bottom would result; and when equilibrium had been restored, the number of the inefficients at the bottom of the Abyss would have been increased by hundreds of thousands.