名词

1. 效率;效能;功效
Efficiency is the quality of being able to do a task successfully, without wasting time or energy.

2. （物理学、工程学中的）效率，功率
In physics and engineering, efficiency is the ratio between the amount of energy a machine needs to make it work, and the amount it produces.

1. skillfulness in avoiding wasted time and effort

e.g. she did the work with great efficiency

2. the ratio of the output to the input of any system