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(n.)
A light helmet, at first open, but later made with a visor.
  

The helmet that evolved out of the cervellaire , a small "skull cap" worn under the great helm , by extending the plate down over the neck and cheeks. Gradually the great helm was discarded altogether in favor of the bascinet because of the superior vision, glancing surface, and lightweight design. Early bascinets had no visors , but by the second quarter of the 14th century they were fitted with Klappvisiers , visors, using a centralized hinge system. Many of these hinges were easily removed, possibly meaning that they were intended to be discarded after the battle was joined. During the 1370s visors began to be attached to the side of the helmet, a more secure attachment system that often allowed the visor to pivot completely back around the helmet, meaning that it might not be lost in battle. During the 1390s steel ventails gradually replaced the mail aventail that had been fitted alongside the klappvisier to defend the neck , creating a new kind of helmet, the great bascinet , popular especially in the Hundred Years War in both France and England. Many examples can be seen in funery effigies of the period. This innovation of hinged neck defenses gradually evolved into the Armet , the dominant helmet of the 15th century. The bascinet itself was popular throughout Europe during the 14th century, showing a great variety of forms within the style. It is now the most popular helmet in the SCA because of the pronounced glancing surface, ease with which a grille may be attached and interchanged with a visor, superior defense for the head and neck, and sleek appearance. See Chronique: The Journal of Chivalry #12 .

See more at Wikipedia.org...

(n.)
A light helmet, at first open, but later made with a visor.
  

The helmet that evolved out of the cervellaire , a small "skull cap" worn under the great helm , by extending the plate down over the neck and cheeks. Gradually the great helm was discarded altogether in favor of the bascinet because of the superior vision, glancing surface, and lightweight design. Early bascinets had no visors , but by the second quarter of the 14th century they were fitted with Klappvisiers , visors, using a centralized hinge system. Many of these hinges were easily removed, possibly meaning that they were intended to be discarded after the battle was joined. During the 1370s visors began to be attached to the side of the helmet, a more secure attachment system that often allowed the visor to pivot completely back around the helmet, meaning that it might not be lost in battle. During the 1390s steel ventails gradually replaced the mail aventail that had been fitted alongside the klappvisier to defend the neck , creating a new kind of helmet, the great bascinet , popular especially in the Hundred Years War in both France and England. Many examples can be seen in funery effigies of the period. This innovation of hinged neck defenses gradually evolved into the Armet , the dominant helmet of the 15th century. The bascinet itself was popular throughout Europe during the 14th century, showing a great variety of forms within the style. It is now the most popular helmet in the SCA because of the pronounced glancing surface, ease with which a grille may be attached and interchanged with a visor, superior defense for the head and neck, and sleek appearance. See Chronique: The Journal of Chivalry #12 .