Defense
From Fallen Sword Wiki
Defense is one of five stats that helps determine the outcomes of a battle.
The other stats are Attack, Armor, Damage, and HP.
Defense increases your ability to block (or evade) an incomming attack and take no damage from it.
A player with high defense will require an attacking player (or creature) to have a high Attack to damage them.
A player's Defense can be raised by the Skill Buff Constitution, as well as raising the base Defense with Evade, Rock Skin, and Aura of Protection.