Formal term for lost items, often used in official contexts such as police reports, station lost-and-found, and legal notices.
I picked up my umbrella at the station's lost-and-found office.
Under the Lost Property Act, the finder must report it promptly.
The station staff reported the umbrella they found as lost property.
The police keep lost property for a set period of time.
He showed his ID and claimed his lost property.