A Japanese term (無駄) meaning “futility; uselessness; wastefulness.” Muda is a key removal-of-waste concept (along with Mura and Muri) in lean manufacturing that focuses on the removal of non-value adding steps. 

The following table illustrates the traditional forms of muda in manufacturing with their equivalence in product development:

Manufacturing Muda Product Development Muda
Transportation Handoffs
Inventory Work in process (WIP)
Motion Task switching
Waiting Delays
Over-processing Gold plating
Over production Extra features
Defects Defects

See also mura, muri.