If you do something efficiently, you do it productively and quickly. When your dentist efficiently examines your teeth, you are grateful because he does a good job and it's all over quickly.
The adverb efficiently has origins in the Latin word efficere, meaning "work out, accomplish." Efficiently can describe any action that's done without wasting time, effort, or materials — and still manages to produce the desired outcome. Today people are using power, fuel, and water more efficiently to conserve natural resources. As a project manager, you efficiently manage your projects so they stay on schedule and under budget.