A type of sword first introduced in the early 1400’s. C.E., It's the hardest type to define with the designation usually meant in terms of a set of qualities that were being introduced to the field in that era, hence the name.
As a generalization, they usually had the same length as long-swords, 40-48 inches, and nearly the same weight, 3-3.5 pounds; but they differed in the switch-hitting handle that could be comfortably used in a one-handed or dual-handed fashion, and the inclusion of annelets and side-rings. These improvements were added to further the new need for better point control and maneuverability to catch up to the advancements in armor and foil them.
Resources:
Medieval Swordsmanship, by John Clements
European Weapons and Armor, by R.E. Oakeshott