Bycocket is a form of headdress popular during the late Middle Ages. It was open at the top, with a brim sloping downwards all around and worn tilted forward or to one side. The term 'bycocket' is derived from the French 'bi-coque', meaning 'two-shelled'. Synonyms for bycocket include 'tournoi' (French for 'tournament') as it was popular among knights during jousting events. It is also known as the 'liripipe' hat due to the long tail at the back of the headwear. Other synonyms include the 'cocktail hat', 'bird's nest', and the 'marguerite'. Bycockets were fashionable during the 14th and 15th centuries, and they are still popular as reenactment headwear today.