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Related to sigma: Six Sigma


1. The 18th letter of the Greek alphabet. See Table at alphabet.
2. A sigma factor.
3. Statistics The standard deviation of a given probability distribution or a given set of data.

[Greek sīgma, of Phoenician origin; see smk in Semitic roots.]

sig′mate′ (-māt′) adj.
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.


1. (Letters of the Alphabet (Foreign)) the 18th letter in the Greek alphabet (Σ, σ, or, when final, ς), a consonant, transliterated as S
2. (Mathematics) maths the symbol Σ, indicating summation of the numbers or quantities indicated
[Greek, of Semitic origin; related to Hebrew samekh]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˈsɪg mə)

n., pl. -mas.
the 18th letter of the Greek alphabet: Σ, σ, ς.
[1600–10; < Latin < Greek sígma]
sig•mate (ˈsɪg mɪt, -meɪt) adj.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.sigma - the 18th letter of the Greek alphabetsigma - the 18th letter of the Greek alphabet
Greek alphabet - the alphabet used by ancient Greeks
alphabetic character, letter of the alphabet, letter - the conventional characters of the alphabet used to represent speech; "his grandmother taught him his letters"
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.


[ˈsɪgmə] nsigma m or f inv
Collins Italian Dictionary 1st Edition © HarperCollins Publishers 1995
References in classic literature ?
The outlying villages, they say, are by them called {kappa omega mu alpha iota}, by the Athenians {delta eta mu iota}: and they assume that Comedians were so named not from {kappa omega mu 'alpha zeta epsilon iota nu}, 'to revel,' but because they wandered from village to village (kappa alpha tau alpha / kappa omega mu alpha sigma), being excluded contemptuously from the city.
Klas Klaas Senior Adviser / Policy Analyst at OECD, SIGMA and Makar Hambaryan, Head of the Department for Internal Financial
The new entity, Countryside Sigma Ltd, will be engaged in the development of residential sites throughout Liverpool.
The term six sigma itself originates from statistical analysis of manufacturing processes.
Under the terms of the agreement, Potomac and Sigma each agreed to vote their respective proxies at the 2012 annual meeting to elect two new directors recommended by Potomac, Eric B.
Benchmark Six Sigma Networking Event gives a platform to six sigma practitioners and upcoming professionals to interact and discuss on various new concepts in the field of Six Sigma and analyzing the old ones.
This paper examines the background of Six Sigma and its derivatives and extensions (for convenience, only the term "Six Sigma" will be used) and explores possible directions for its development in industry in the light of its past development.
However, it is now being increasingly recognized, there is a way forward Six Sigma programs, which encompass existing concepts and established statistical approaches within a systematic and quantifiable project based improvement methodology.
Sigma, Australia's biggest drugs distributor, closed the week up 5 Australian cents, or 12%, at 46 Australian cents in Sydney trading.
In a nutshell, six sigma (6-sigma) can be discussed at three levels: as a management system, as a methodology, and as a metric (a statistic).
Six Sigma is a total quality management (TQM) technique pioneered by and applied to Motorola processes in the 1980s by Bill Smith, a Motorola engineer who became known as "the father of Six Sigma." Since then, other companies, such as Bank of America, Honeywell International, Raytheon, and General Electric, have taken these learned processes and expanded them.