Six Sigma definitions – wisefaq.com

Some Six Sigma definitions which I’ve collected over time.

Term	Definition
CTQs	Critical To Quality. The sort list of the most important customer wants.
Customer	Any internal/external person/organisation who receives the output of a process.
Customer Requirements	The needs and expectations of the customer. Which is translated into measurable terms. Used in the process to ensure compliance with customers’ needs.
Defect	Any occurrence or instance where the product/service fails to meet the customers requirements.
Defect opportunity	A type of potential defect on a unit of throughput/output, which is important to the customer.
DPMO	Defects Per Million Opportunities. Calculation used in process improvement initiatives indicating the amount of defects in a process.
Sigma	A statistical term that measures how much a process varies from perfection, based on the DPMO.
Six Sigma	A level of process performance equalling 3.4 DPMO.
Standard deviation	Statistical measure of how much variation there is in a set of data.
Variation	Change/fluctuation of a specific characteristic. Determines process stability/predictability.