Point spread is the use of attribute points to define the level in an attribute when describing builds. Using the level to define an attributes level number can be confusing in Guild Wars because runes and headpiece armor raise the attribute level above its true amount. Attribute points, on the other hand, never change due to what you wear.
Some players in PvP prefer using point spread when describing builds. With the introduction of the skill template system to Guild Wars it has become an antiquated way of describing builds to one another in chat.