Efficient (adjective)
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.”
Efficient (adjective)
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.”
Efficient (adjective)
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”
Efficient (adjective)
(proscribed, old use) Effective.
Proficient (adjective)
Good at something; skilled; fluent; practiced, especially in relation to a task or skill.
“He was a proficient writer with an interest in human nature.”
Proficient (noun)
An expert.
Efficient (adjective)
(of a system or machine) achieving maximum productivity with minimum wasted effort or expense
“more efficient processing of information”
Efficient (adjective)
preventing the wasteful use of a particular resource
“an energy-efficient heating system”
Efficient (adjective)
(of a person) working in a well-organized and competent way
“an efficient administrator”
Proficient (adjective)
competent or skilled in doing or using something
“I was proficient at my job”
“she felt reasonably proficient in Italian”
Proficient (noun)
a person who is proficient
“he became a proficient in Latin and Greek”