efficientadj/ɪˈfɪʃənt/

• 1

  Making good, thorough, or careful use of resources; not consuming extra. Especially, making good use of time or energy.

  • An efficient process would automate all the routine work.
  • Our cleaners are almost too efficient: they throw away anything left out on a desk.
• 2

  Expressing the proportion of consumed energy that was successfully used in a process; the ratio of useful output to total input.

  • The motor is only 20% efficient at that temperature.
• 3

  Causing effects, producing results; bringing into being; initiating change (rare except in philosophical and legal expression efficient cause = causative factor or agent).

  • Ownership, maintenance, or use of the automobile need not be the direct and efficient cause of the injury sustained
  • It was well said of Plotinus, that the stars were significant, but not efficient.
• 4

  effective, efficacious

  • Ye wake no more to anguish;‥ ye have borne The Chosen, the Destroyer!‥ soon his hand Shall strike the efficient blow; Soon shaking off your penal forms, shall ye, With songs of joy, amid the Eden groves, Hymn the Deliverer’s praise!
  • The Efficient Cause is that from which emanates the force that produces the Effect

efficientnoun/ɪˈfɪʃənt/

• 1

  obsoleteA cause; something that causes an effect.

  • Some are without efficient, as God; others without matter, as Angels […].
  • This implies, that something happens without a cause. If it should be said, that motive in this case is not the efficient of the action or doing — this is granted; but at the same time, for reasons already given, it is denied, that the man himself is the efficient cause of it.