chew the cud

The phrase "chew the cud" refers to the act of ruminant animals such as cows, sheep, and goats regurgitating and re-chewing their partially digested food. It is a natural process of digestion that helps break down the plant fibers further, aiding in better nutrient absorption and digestion. In a figurative sense, the phrase can also refer to someone deep in thought or pondering over something.