different between efficiency vs deftness

English

From Latin efficientia.

efficiency (countable and uncountable, plural efficiencies)

The extent to which time is well used for the intended task.
Antonyms: inefficiency, wastefulness
(dated) The quality of producing an effect or effects.
- 1594, Richard Hooker, Of the Lawes of Ecclesiastical Politie
  The manner of this divine efficiency being far above us.
The extent to which a resource, such as electricity, is used for the intended purpose; the ratio of useful work to energy expended.
Antonyms: inefficiency, wastefulness
(US) A one-room apartment.
Synonyms: efficiency apartment, (UK, Ireland) bedsit

deft +? -ness

deftness (usually uncountable, plural deftnesses)

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