Definition of "churn"

churn

/tʃɜːn/

verb
third-person singular simple present churns, present participle churning, simple past and past participle churned
1. (transitive) To agitate rapidly and repetitively, or to stir with a rowing or rocking motion; generally applies to liquids, notably cream.
  Quotations
  Churned in his teeth, the foamy venom rose.
  1717, Joseph Addison, Metamorphoses
2. (transitive, figuratively) To produce excessive and sometimes undesirable or unproductive activity or motion.
  Quotations
  The slope of the terrain, shaped like a funnel, squeezed the growing swell of churning snow into a steep, twisting gorge.
  2012, John Branch, “Snow Fall: The Avalanche at Tunnel Creek”, in New York Times‎
3. (intransitive) To move rapidly and repetitively with a rocking motion; to tumble, mix or shake.
4. (of a customer) To stop using a company's product or service.
5. (informal, travel, aviation) To repeatedly cancel and rebook a reservation in order to refresh ticket time limits or other fare rule restrictions.
6. (US, informal, finance, travel) To continually sign up for new credit cards in order to earn signup bonuses, airline miles, and other benefits.
7. (finance) To carry out wash sales in order to make the market appear more active than it really is.
noun
countable and uncountable, plural churns
1. A vessel used for churning, especially for producing butter.
2. A milk churn (container for the transportation of milk).
  Quotations
  In the old days, milk trains consisted entirely of vans loaded with ten-gallon churns. When filled, these churns weigh 130 lb. each and their manipulation is an art. [...] Like the tank wagons, the churns are dairy property, but farmers often have other ideas, and find their own uses for them—it has not been unknown for dairy inspectors to find missing churns tucked away in an unsuspected corner of a farmhouse, filled to the brim with banknotes!
  1959 March, R. C. Riley, “Home with the milk”, in Trains Illustrated, page 155
3. Customer attrition; the phenomenon or rate of customers leaving a company.
4. (telecommunications) The time when a consumer switches his/her service provider.
5. (telecommunications) The mass of people who are ready to switch carriers.
6. Cyclic activity that achieves nothing.
  Quotations
  I wished my brain would shut up and knew that soon I'd have to start tidying, but first I needed to rest, so I tried to quell the pointless churn behind my eyes and kept on trying (in a minute) until Vicky came back home.
  2007, Hari Kunzru, My Revolutions, page 102
  Getting the right manager has just been made more difficult by not having Champions League to offer. There will also be a huge churn of players after the lavish, unrewarding outlay this season.
  2023 April 18, Phil McNulty, “Chelsea Champions League exit: Where do 'disjointed, broken' Blues go from here?”, in BBC Sport‎
7. (historical) The last grain cut at harvest; kern.