Stories We Like: A Guide to the Comma
Old English cyrin, from Proto-Germanic *kernjon (cf. Old Norse kirna, Swedish kärna, Danish kjerne, Dutch karn, Middle High German kern); probably akin to cyrnel "kernel" (see kernel) and describing the "grainy" appearance of churned cream.
mid-15c., chyrnen, from churn (n.). Extended senses are from late 17c. Intransitive sense is from 1735. Related: Churned; churning. To churn out, of writing, is from 1902.
To artificially increase the level of activity in a law firm, insurance company, or other enterprise in order to increase commissions, feign busyness, etc: Policyholders have launched class-action suits alleging churning (1940s+)
device for making butter. The earliest churns were goatskins or other primitive containers in which cream could be agitated. The dash churn, familiar to farm homes for centuries, consisted of a tall, narrow, nearly cylindrical stone or wood tub fitted with a wooden cover; the cream was agitated by a hand-operated vertical wooden plunger, or dash. Another type, widely used in the 19th century, was shaped like a small barrel and mounted in a framework. Operation of a hand crank caused the barrel to revolve end over end