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n. pl. ef·fi·cien·cies
a. The quality or property of being efficient.
b. The degree to which this quality is exercised: The program was implemented with great efficiency and speed.
a. The ratio of the effective or useful output to the total input in any system.
b. The ratio of the energy delivered by a machine to the energy supplied for its operation.
3. An efficiency apartment.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


n, pl -cies
1. the quality or state of being efficient; competence; effectiveness
2. (General Physics) the ratio of the useful work done by a machine, engine, device, etc, to the energy supplied to it, often expressed as a percentage. See also thermal efficiency
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ɪˈfɪʃ ən si)

n., pl. -cies.
1. the state or quality of being efficient.
2. accomplishment of or ability to accomplish a job with a minimum expenditure of time and effort.
3. the ratio of the work done by a machine to the energy supplied to it, usu. expressed as a percentage.
[1585–95; < Latin]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.



cooking with gas Operating at maximum efficiency; performing well, functioning smoothly; really in the groove or on the right track. The expression probably comes from the efficiency of gas as a cooking medium (as contrasted with coal, wood, kerosene, electricity, etc.). Occasionally the phrase is jocularly updated by variants such as cooking with electricity or cooking with radar.

hit on all six To run smoothly; to function properly; to work to one’s fullest capacity; to be in physically fit and trim condition. This Americanism was originally used in speaking of internal combustion engines, specifically the functioning of the cylinders, which often misfired in earlier cars. When the figurative use gained currency, the word cylinder was dropped from the end of the expression. Variants include hit on all four and other multiples of two.

Modern science offers you a natural means to keep you “hitting on all six”—every minute of the day. (Saturday Evening Post, March 10, 1928)

in the groove In full swing, functioning smoothly, in top form. This U.S. slang expression was coined in the jazz age. Groove originally referred to the grooves of phonograph records. In the 1930s and ’40s, in the groove meant to play jazz music fervently and expertly, or to appreciate such music and by association be considered “hep” and sophisticated.

The jazz musicians gave no grandstand performances; they simply got a great burn from playing in the groove. (Fortune, August, 1933)

Eventually in the groove and groovy grew to mean ‘up-to-date’ or ‘fashionable,’ although this use is now being phased out of current slang. When in the groove is used, as in the following quotation from Webster’s Third, it emphasizes the quality of being in top form, rather than sophistication or fashionableness.

It made no difference, when he was in the groove, what he chose to talk about. (Henry Miller)

just like New York This American slang expression, usually an isolated comment on successful performance, has a wide range of equally vague equivalents such as right on, great, nice going, way to go. The reference is to New York City as the epitome of success, society, and fashion.

Picturesque Expressions: A Thematic Dictionary, 1st Edition. © 1980 The Gale Group, Inc. All rights reserved.


The ratio of a machine’s energy output to energy input.
Dictionary of Unfamiliar Words by Diagram Group Copyright © 2008 by Diagram Visual Information Limited
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.efficiency - the ratio of the output to the input of any system
ratio - the relative magnitudes of two quantities (usually expressed as a quotient)
figure of merit - a numerical expression representing the efficiency of a given system, material, or procedure
2.efficiency - skillfulness in avoiding wasted time and effort; "she did the work with great efficiency"
skillfulness - the state of being cognitively skillful
economy - the efficient use of resources; "economy of effort"
inefficiency - unskillfulness resulting from a lack of efficiency
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.


Collins Thesaurus of the English Language – Complete and Unabridged 2nd Edition. 2002 © HarperCollins Publishers 1995, 2002


1. The quality of being efficient:
2. The power or capacity to produce a desired result:
The American Heritage® Roget's Thesaurus. Copyright © 2013, 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
كَفاءَه، مَقْدِرَه، فاعِلِيَّه
dugnaîur, skilvirkni, nÿtni


[ɪˈfɪʃənsɪ] N
1. [of person, manager] → eficiencia f; [of method, remedy, product, army] → eficacia f
2. (Mech, Phys) [of machine] → rendimiento m
Collins Spanish Dictionary - Complete and Unabridged 8th Edition 2005 © William Collins Sons & Co. Ltd. 1971, 1988 © HarperCollins Publishers 1992, 1993, 1996, 1997, 2000, 2003, 2005


n [person] → efficacité f; [method] → efficacité f; [institution] → bon fonctionnement m; [activity] → productivité f; [machine] → rendement m energy efficiency, fuel efficiency
modif [gains] → de rendement
efficiency savings → économies fpl de fonctionnementefficiency apartment n (US)studio m
Collins English/French Electronic Resource. © HarperCollins Publishers 2005


n (of person)Fähigkeit f, → Tüchtigkeit f; (of machine, factory, organization, system)Leistungsfähigkeit f; (of method)Wirksamkeit f; (of engine) (= power)Leistungsfähigkeit f; (= economy)Sparsamkeit f; (of service) → Effizienz f (geh); (of use) → Rationalität f; jobs were lost as part of an efficiency driveStellen wurden wegrationalisiert; software that improves the efficiency of translatorsSoftware, die die Leistungsfähigkeit von Übersetzern erhöht
Collins German Dictionary – Complete and Unabridged 7th Edition 2005. © William Collins Sons & Co. Ltd. 1980 © HarperCollins Publishers 1991, 1997, 1999, 2004, 2005, 2007


[ɪˈfɪʃnsɪ] n (see adj) → efficienza, efficacia, rendimento
Collins Italian Dictionary 1st Edition © HarperCollins Publishers 1995


(iˈfiʃənt) adjective
1. (of a person) capable; skilful. a very efficient secretary.
2. (of an action, tool etc) producing (quick and) satisfactory results. The new lawn mower is much more efficient than the old one.
efˈficiently adverb
efˈficiency noun
Kernerman English Multilingual Dictionary © 2006-2013 K Dictionaries Ltd.


n. eficiencia, competencia.
English-Spanish Medical Dictionary © Farlex 2012
References in classic literature ?
"It shall not be said that I sacrificed efficiency to economy," said the Governor.
An enlightened zeal for the energy and efficiency of government will be stigmatized as the offspring of a temper fond of despotic power and hostile to the principles of liberty.
To insure the greatest efficiency in the dart, the harpooneers of this world must start to their feet from out of idleness, and not from out of toil.
From the girls and women near her, all swinging irons steadily but at high pace, came quick glances, and labor efficiency suffered to the extent of a score of suspended or inadequate movements.
Efficiency of a practically flawless kind may be reached naturally in the struggle for bread.
With a large business there is always less waste and greater efficiency."
A man of soft civilization, sitting at a desk, would have grown lean and woe-begone on the fare that kept Kama and Daylight at the top-notch of physical efficiency. They knew, as the man at the desk never knows, what it is to be normally hungry all the time, so that they could eat any time.
Zenobia, though doubtful of the girl's efficiency, was tempted by the freedom to find fault without much risk of losing her; and so Mattie came to Starkfield.
He went up to the map and speaking rapidly began proving that no eventuality could alter the efficiency of the Drissa camp, that everything had been foreseen, and that if the enemy were really going to outflank it, the enemy would inevitably be destroyed.
An outcast himself from the pack of the part-grown dogs, his sanguinary methods and remarkable efficiency made the pack pay for its persecution of him.
Before the public he would have liked to vindicate the efficiency of his department by establishing the identity of that man.
The efficiency of these two men was greatly increased by a third--Thomas D.