Churn

Churn, a word whose cognate forms appear in many languages, denotes the vessel in which cream or milk is agitated in order to separate the particles and induce the formation of butter. There are many varieties of churn, from the old-fashioned upright one, in which a vertical rod with dashers attached is worked in a vertical direction, to the ordinary barrel-shaped churn, which sometimes consists of a stationary cylinder in which dashers fixed upon a horizontal axis are turned by means of a handle, sometimes of a movable barrel which is itself made to revolve. There are also modifications of these principles. The word is also used metaphorically of the violent agitation of any substance. Thus, the paddle-wheel of a steamer is said to churn the waves to foam.