Opera hat, also known as a topper or a top hat, is a type of hat that was popularised during the 19th century. It is characterised by its tall, cylindrical shape and rounded crown. The top of the hat is typically made of a hard material such as silk or wool felt, while the brim is narrow. The opera hat was commonly worn by gentlemen during formal occasions, such as weddings and operas. Other synonyms for the opera hat include a high hat, silk hat, stovepipe hat, and chimney pot hat. Despite a steady decline in popularity over the years, the opera hat remains a symbol of formal elegance and sophistication.