In computer games, a buff often refers to a bonus given to a game character that extends their ability. A buff is usually gained from an in-game item, another player’s ability, or a spell. For example, in the MMORPG game EverQuest, a popular buff is the SoW (Spirit of Wolf), which increases the movement speed of your character.
The opposite of a buff is a debuff, which decreases a character’s attributes or abilities. For example, a mana debuff may reduce the character’s overall mana, preventing them from casting as many spells.
DoT, Game terms