Definition of Six Sigma in US English:

Six Sigma


trademark in US
  • A set of management techniques intended to improve business processes by greatly reducing the probability that an error or defect will occur.

    ‘the company has long used Six Sigma to analyze its manufacturing processes’
    as modifier ‘Six Sigma standards’
    • ‘Six Sigma is not just for manufacturing.’
    • ‘We turned to Six Sigma for a proven management model.’
    • ‘All employees are required to be trained as Six Sigma green belts, the first level of proficiency.’
    • ‘Statistics selected for on-farm use are consistent with Six Sigma theory.’
    • ‘Her company is working on ways to quantify the bottom-line effect of its advertising spending by coupling a variety of traditional metrics with Six Sigma methodology.’
    • ‘Six Sigma teams facilitated the execution and implementation of these products.’
    • ‘We adopted Six Sigma quality-management systems that ensured that every process would be robust enough to turn whoever was involved in it into a competent employee.’
    • ‘Six Sigma principles were utilized to develop a system for precision farming to improve nutrient management.’
    • ‘Six Sigma is a broad discipline, but it is based on some valuable analytical and quality tools.’
    • ‘It has two Six Sigma black belts on staff and boasts, "Quality isn't something we add at the end of the line!"’


1980s: from the statistical term for six standard deviations (see sigma), a key measure for this method of quality control.