The Collaborative International Dictionary of English v.0.48:
Churn \Churn\, v. t. [imp. & p. p. Churned (ch[^u]rnd); p. pr.
& vb. n. Churning.] [OE. chernen, AS. cernan; akin to LG.
karnen, G. kernen, D. karnen, Dan. kierne, Sw. k[aum]rna, 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.