A more thorough explanation:

Mariner's hypothec is a type of mortgage given to a creditor on a ship to secure a debt. It is also a lien that a seaman, freighter, or repairer can assert against a ship for payment of wages or other sums due. Additionally, it can be a shipowner's lien against the ship's cargo for the freight costs.

For example, if a seaman is not paid their wages, they can assert a mariner's hypothec against the ship they worked on to secure payment. Similarly, if a shipowner is not paid the freight costs for transporting cargo, they can assert a mariner's hypothec against the cargo.

Overall, mariner's hypothec is a legal mechanism that provides security for debts related to ships and their operations.