Ruminant (noun)

1. An animal, such as a cow, sheep, or giraffe, that chews its cud, meaning it regurgitates and re-chews food that has been previously swallowed.
2. A person who reflects deeply on something, especially one who is prone to dwelling on negative thoughts or past events.

Origin:

From the latin word ruminare meaning to chew over, and the suffix -ant, meaning a person or animal that does something.

Examples:

1. The cow is a common ruminant animal.
2. Sheep and goats are also ruminant animals.
3. The giraffe is an unusual ruminant animal because of its long neck.
4. He was a ruminant person who constantly dwelled on past mistakes.
5. She was a ruminant person who constantly overthought her decisions.