If you ruminate on something, you think about it very carefully.
例句
He ruminated on the terrible wastage that typified American life...他认真地考虑了美国生活中典型的严重浪费问题。Obsessional personalities commonly ruminate excessively about death.有强迫症的人通常过多地思考死亡的问题。
VERB
（动物）反刍
When animals ruminate, they bring food back from their stomach into their mouth and chew it again.
例句
He wanted to have a look at the two oxen, both ruminating without raising their eyes.他想看看那两头牛，它们都在反刍，眼睛都不抬一下。