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Table 1 Glossary of the main terminology applied in the Toyota Production System and lean manufacturing

From: Lean manufacturing and Toyota Production System terminology applied to the procurement of vascular stents in interventional radiology

Jidoka (自働化)

Using intelligent automation—sometimes also referred to as “autonomation” or automation with a human touch—to promote flow. This term describes a quality control supervisory process that prevents the production of continuous defective products by detecting production abnormality, stopping it, immediately fixing or correcting it and investigating the root cause in order to prevent it from reoccurring.

Heijunka (平準化)

The Heijunka box is a visual production smoothing or production levelling mechanism to produce intermediate goods at a constant rate, thus allowing further processing to be carried out at a constant and predictable rate that distributes the finishing schedule into small time increments. The heijunka box is generally a wall schedule that is divided into a grid of boxes, each one representing a specific unit of time; lines are drawn down the schedule to break it into columns of days or weeks.

Kaizen (改善)

The term connotes “change for the better” or “improvement”. The Japanese character “kai” stands for “take apart,” and “zen” connotes “make good.” An adequate English translation is “continuous process improvement”. Kaizen is a quality strategy that is aimed at eliminating waste by eliminating any activities that add cost without adding value.

Kaizen event

A kaizen event or “kaizen blitz” is a team event dedicated to quickly implementing a lean manufacturing method in a particular area in a very short time period.

Kanban (看板)

“Kan” means visual, and “ban” means card or board; the term implies an inventory control method that historically used cards to signal the need for an item. However, other devices such as plastic markers (Kanban squares) or balls (e.g. golf balls) or an empty transport trolley can also be used to trigger the movement, production or supply of a unit in a factory. Kanban is a textbook example of a demand-driven (economic production) pull system.


Short form for lean manufacturing—minimising waste and maximising flow.

Muda (無駄)

In the literature the term is translated as “waste” but more precisely implies any human activity that absorbs resources without creating value. The Japanese antonym of “muda” can be translated as “usefulness”, which may assist in more adequately identifying the meaning of the Japanese term: anything in a work process that adds cost or time without adding value can be regarded as “muda.”

Poka-yoke (ポカヨケ)

Poka-yoke means “mistake-proofing”—avoiding (yokeru) inadvertent errors (poka) is a behaviour-shaping constraint, or a method of preventing errors by putting limits on how an operation can be performed in order to force the correct completion of the operation. The original term was Baka-yoke, but as this more precisely connotes "fool-proofing" (or “idiot proofing”) the name was modified to the more companionable Poka-yoke.