therblig
n. a unit of movement sometimes used to describe and record industrial operations for the purposes of time and motion studies. It represents any one of the 18 fundamental, standardized activities involved in such operations: search, find, select, grasp, hold, position, assemble, use, disassemble, inspect, transport loaded, transport unloaded, pre-position for next operation, release load, unavoidable delay, avoidable delay, plan, and rest to overcome fatigue. [coined by U.S. engineer and efficiency expert Frank B. Gilbreth (1868–1924) and Lillian Moller Gilbreth, from a backward spelling of their surname]