Churn (chûrn), n. [OE. chirne, cherne, AS. ceren, cyrin; akin to D. karn, Dan. kierne. See Churn, v. t.] A vessel in which milk or cream is stirred, beaten, or otherwise agitated (as by a plunging or revolving dasher) in order to separate the oily globules from the other parts, and obtain butter.

Churn, v. t. [imp. & p. p. Churned (chûrnd); p. pr. & vb. n. Churning.] [OE. chernen, AS. cernan; akin to LG. karnen, G. kernen, D. karnen, Dan. kierne, Sw. kärna, and also to E. corn, kernel, the meaning coming from the idea of extracting the kernel or marrow. See Kernel.] 1. To stir, beat, or agitate, as milk or cream in a churn, in order to make butter.

2. To shake or agitate with violence.

Churned in his teeth, the foamy venom rose.
Addison.

Churn, v. i. To perform the operation of churning.

• To agitate rapidly and repetitively, or to stir with a rowing or rocking motion; generally applies to liquids, notably cream.
       Now the cream is churned to make butter.
  
• (figuratively) To produce excessive and sometimes undesirable or unproductive activity or motion.
  
• To move rapidly and repetitively with a rocking motion; to tumble, mix or shake.
       I was so nervous my stomach was churning.
  
• A vessel used for churning.
       a butter churn
  
• In the telecommunication sector (telecommunications):
        The time when a consumer switches his/her service provider.
        The mass of people who are ready to switch carriers.