six sigma six sig‧ma [ˌsɪks ˈsɪgmə] noun [uncountable]
STATISTICS when the number of faults in a product or process is reduced to just over three per million:
• Six sigma means one is achieving process perfection 99. 9 percent of the time.
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six sigma UK US (also Six Sigma, six-sigma) noun [U] PRODUCTION, MANAGEMENT
► a method for improving production processes so that the quality of products is nearly always perfect: »
We have been improving efficiency and implementing lean manufacturing techniques, including Six Sigma.
»six sigma methods/principles/products
Financial and business terms. 2012.