The degree to which work, processes, or systems achieve results without waste; effectiveness in terms of time, effort, or resources.
効率を上げるために業務フローを見直した。
We reviewed the workflow to improve efficiency.
この機械は電力消費が少なく、効率がいい。
This machine has low power consumption and high efficiency.
能率も大事だが、効率的に休むことも必要だ。
Productivity is important, but resting efficiently is also necessary.
効率（こうりつ）よりも正確さが求められる作業だ。
This task demands accuracy more than efficiency.