A more thorough explanation:

Definition: Quidam is a Latin term that means "somebody." In French law, it is used to refer to a person whose name is unknown.

• "The suspect was described as a quidam, with no identifiable features."
• "The witness saw a quidam running away from the scene of the crime."

These examples illustrate how the term quidam is used to refer to an unknown person. In both cases, the person being described is not known by name or any other identifying characteristics. The term is often used in legal contexts when the identity of a person is not known, but they are still relevant to a case or investigation.