A small, hemmed square of fabric, typically silk, linen, or cotton, worn exclusively for aesthetic purposes in the upper breast pocket of a blazer or suit jacket. Unlike a handkerchief, it is not intended for utilitarian use. It is folded in various styles, such as the presidential or puff fold, to add color and texture to tailored menswear.
Heard on the job
The groom's party is wearing navy suits with a white linen pocket square in a crisp flat fold.