efficient in WordNet English dictionary

1. able to accomplish a purpose; functioning effectively
   "people who will do nothing unless they get something out of it for themselves are often highly effective persons..."-G.B.Shaw; "effective personnel"; "an efficient secretary"; "the efficient cause of the revolution"
   effective  efficient 
   
2. being effective without wasting time or effort or expense
   "an efficient production manager"; "efficient engines save gas"
   efficient