noun. a unit of motion, at times, utilized to depict and document industrial functions for the purpose of time and movement analyses. It symbolizes any one of the 18 basic, standardized activities comprised in such functions: plan, search, select, grasp, find, position, assemble, use, hold, disassemble, transport loaded, inspect, transport unloaded, release load, pre-position for next operation, unavoidable delay, rest to overcome fatigue, and avoidable delay.