The term 'Sinatra Trademark' refers to the iconic FEDORA hat worn by Frank Sinatra, the legendary American singer and actor. The FEDORA was a popular style of hat in the early 20th century, and Sinatra made it his signature look. He was often seen wearing the hat in public, and it became synonymous with his image. The term 'Sinatra Trademark' is used to refer to the FEDORA hat, which is also known as a trilby or a homburg.