Definition:
In Japanese, the term ‘Mura’ means unevenness or inconsistency in physical matter or human spiritual condition. In Kanban, Mura is reduced by equipping the process with the exact part, at the exact time, in the exact amount. Mura in Japanese means irregularity, lack of uniformity or non-uniformity, inequality and it is also included as a key concept in Toyota Production System (TPS). Mudra is one of the three types of waste i.e., (Muda, Mura and Muri).
In Toyota waste reduction is one of the effective to increase profitability and eliminate the less profitable resources. Toyota has adopted these three words as part of their process of product improvement program,as they are very familiar with the common Japanese word usage.
Further Reading:
The Toyota Way Fieldbook by Liker, David Meier, Liker