noun
A device for agitating milk or cream to make butter. Technical or historical term; in modern contexts, often refers to a butter churn.
昔は撹乳器を使って手作業でバターを作っていた。
In the past, people made butter by hand using a churn.
Compound of 撹 (かく, 'stir, agitate') + 乳 (にゅう, 'milk') + 器 (き, 'device, vessel'). Literally 'milk-agitating device'.