The word "churn" refers to the process of shaking or stirring something vigorously, often used in the context of making butter from cream. It can also be applied more broadly to describe situations where something is in a state of constant change or activity, such as in a business context where customer turnover is high.
The word "churn" originates from the Old English "cyren," which meant to turn over or agitate. This evolved into the Middle English "churnen," referring specifically to the action of turning cream to make butter.