A more thorough explanation:

Definition: Concussio (pronounced kuhn-KUH-shio) is a term from Roman law that refers to the act of extorting money or gifts from someone by threatening them with violence. In modern civil-law contexts, the term is often referred to as concussion.

Examples: An example of concussio would be a mafia boss demanding money from a business owner in exchange for "protection" from harm. Another example would be a corrupt government official demanding bribes from citizens in exchange for performing their duties.

These examples illustrate the definition of concussio because in both cases, someone is using the threat of violence or harm to extort money or gifts from another person. This is illegal and unethical behavior that is punishable by law.