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general::
Phrase(s): ruminate about something [and] ruminate on something
to ponder and think about something. (Alludes to a cow, relaxing and chewing its cud, as if it is thinking.) • He sat, ruminating about the events of the day, humming and eating peanuts. • Let me ruminate on this a little bit.
McGrawhill's American Idioms And Phrasal Verbs