Kite
A technique for fighting which involves staying out of range of an enemy while simultaneously doing damage to it
Kara
Karazhan, a 10-player raid and the first level 70 raid instance. Located in Deadwind Pass.
IRL
In Real Life
INT
Intelligence, a base statistic
Instance
A dungeon where you will load into your own copy of the dungeon with your group. Only you and your group will be in your copy of the dungeon. Another group that enters the same area will enter their own copy of the dungeon.
Inc
Incoming. This means enemies are coming. Used when pulling or to warn others of adds or patrols.
IF
Ironforge, home of the Dwarves
HS
Healthstone, a warlock conjured item that restores health to the user
HP
Health, Health Points, Hit Points. When these are reduced to 0, the character or NPC dies.
Gruul
The second and final boss encounter of Gruul's Lair, the first 25-man raid instance in the Burning Crusade