Parry allows the character to use his/her weapon to increase his/her Dodge rating in combat.  It provides a Dodge Bonus as long as the character is wielding a weapon that the character has selected as a Weapon Ability.  For instance, if a character has Parry Rating 12 and has “Staff Abilities” and “Sword Abilities” purchased as well, whenever he has a staff or a one-handed sword in his hand, he receives a bonus of 12 to the character’s Dodge Rating in combat.