These abbreviations are commonly used in game to describe situations and events. Expect to see these frequently used.
Zone/City Specific:
BS = Burning Steppes
DWM = Dustwallow Marsh
DW = Duskwood
EPL = Eastern Plaguelands
IF = Ironforge
LM = Loch Modan
MH = Menethill Harbor
SG = Searing Gorge
SS = Southshore
STV = Stranglethorn Vale
SW = Stormwind City
WF = Westfall
WPL = Western Plaguelands
Arathi Highlands and Hillsbrad Foothills are commonly referred to by first word
Instance Specific:
BRD = Blackrock Depths
BRM = Blackrock Mountain
BRS = Blackrock Spire
DM = Deadmines
Gnomer = Gnomeregan
LBRS = Lower Blackrock Spire
MC = Molten Core
RFD = Razorfen Downs
RFK = Razorfen Kraul
Scholo = Scholomance
Strat = Stratholme
SM = Scarlet Monastery
UBRS = Upper Blackrock Spire
ZF = Zul’Farrak
Game Specific:
AE = Area Effect
AoE = Area of Effect
Aggro = Range of Aggressive Pull
BoE = Bind on Equip
BoP = Bind on Pickup
GL = Group Loot
MA = Main Assist
ML = Master Looter
MT = Main Tank
NBG = Need Before Greed
RR = Round Robin