Definition of wind down

The phrase "wind down" is a figurative expression that has its origins in the mechanical and technical arena. It was originally used to describe the process of gradually decreasing the speed or intensity of any mechanical device or system, either to prepare it for shutdown or to allow it to return to its starting state. In the late 19th century, as industrialization deepened, machines integrated into the factories, and transportation networks grew more complex, engineers devised new ways to manage and monitor them. The concepts of accelerating, decelerating, and otherwise balancing the rate of operation of these machines became increasingly familiar vocabulary among the technical community. By the early 20th century, as the cognitive and behavioral sciences began to develop such jargon as "relax", "unwind", and "blow off steam", the expression "wind down" entered the vernacular to convey the idea of easing oneself into a state of serenity or calmness after an intense or trying activity, promoting decreased levels of arousal and anxiety. Interestingly, whilst the literal use of "wind down" remains prevalent across various fields, such as in regard to machinery or electric appliances, its colloquial meaning has developed into one of relaxing or quieting one's mind after stress in daily speech.