A more thorough explanation:

Definition: A bigamus is a person who commits bigamy, which means marrying someone while still being legally married to someone else. It can also refer to a man who marries a widow or remarries.

Examples:

• John was arrested for being a bigamus because he had two wives at the same time.
• After his first wife died, Tom became a bigamus when he married his second wife without getting a legal divorce.

These examples illustrate how a bigamus is someone who enters into a marriage while still being legally married to someone else or who marries a widow without following the proper legal procedures.