There are a lot of terms that are specific to Lean and Six Sigma. If you are unsure about the meaning of a term, please feel free to check our Lean and Six Sigma Glossary for a definition. If you do not find the term you are looking for, please contact us. We would be happy to answer your questions, and we may add your term to the glossary in the future.


DMAIC phase where solutions and ideas are creatively generated and decided upon. Once a problem has been fully identified, measured, and analyzed, potential solutions can be determined to solve the problem in the problem statement and support the goal statement. See also Charter.

Hypothesis statement

A complete description of the suspected cause(s) of a process problem.

Histogram or Frequency Plot

Chart used to graphically represents the frequency, distribution and “centeredness” of a population.


Any time in a process when one person (or job title) passes on the item moving through the process to another person; potential to add defects, time, and cost to a process.


Any product, service, or piece of information that comes into the process from a supplier.

Input measures

Measures related to and describing the input into a process; predictors of output measures.

Judgment sampling

Approach that involves making educated guesses about which items or people are representative of a whole, generally to be avoided.


Standard and guideline used to certify organizations as competent in defining and adhering to documented processes; mostly associated with quality assurance systems, not quality improvement.


Fundamental changes in daily behaviors, attitudes, and practices that make changes “permanent”, cultural adaptation of changes implemented by Process Improvement, Design or Redesign-including complex business systems such as HR, MIS, Training, etc.