Add (WoW)  

An Add refers to an additional mob unintentionally pulled when fighting.

This can be due to a bad pull which resulted in grabbing more mobs than intended. It can refer to picking up mobs in the middle of battle for various reasons such as a player got feared into the aggro range of another set of mobs, a running mob went and got friends, or a pat came by and joined the fray.

World of Warcraft Wikibase™