It refers to a sword used as part of knightly battle dress. The arming sword was also known as an arming doublet because it doubled as both body armor and a weapon.
The arming sword of the European High Middle Ages was a straight, double-edged weapon with a single-handed, cruciform hilt. It was typically wielded in one hand, though it could also be used with two hands on occasion.
The arming sword is a medieval sword that is believed to have originated in France. It’s single-handed and uses a cruciform hilt. Its blade was single-edged, straight, and of moderate length. It had a sharp point and an edge on both sides of the blade which made it difficult to block.
There are many types of medieval swords; some of which were used as tools, others as symbols of power. In Europe during the High Middle Ages, one such type was the arming sword. While not as long or heavy as other medieval swords, it had enough weight to thrust at close range and it was sturdy enough to parry blows from heavier weapons like axes and maces.
Medieval swords were not just used in warfare, they were also used in jousting tournaments and other forms of martial arts. They were so important that they became a symbol of one’s nobility. Knights would wear their swords on the right side, opposite to what we are accustomed to today.