The following is a list of the abbreviations and acronyms used by Cast Members and folks on the internet. Some abbreviations have multiple meanings and some destinations have multiple abbreviations.

AA - The American Adventure
AA - Audio-Animatronics [The *robot* characters in the attractions.]
AC - Adventurers Club
ADR - Advance Dining Reservation
AK - Disney's Animal Kingdom
AKL - Animal Kingdom Lodge
AKV - Disney's Animal Kingdom Villas [a DVC Resort]
AP - Annual Pass
AP - Artist Point
APer - Annual Passholder
AS - Disney's All-Star Sports Resort
ASM or ASMu - Disney's All-Star Music Resort
ASMV or ASMo- Disney's All-Star Movies Resort

BatB - "Beauty and the Beast" - Live on Stage
B&C - Beaches & Cream at the Beach Club
BB - Blizzard Beach
BC - Beach Club Resort
BCV - Beach Club Villas [a DVC Resort]
BTM - Big Thunder Mountain Railroad
BTMR - Big Thunder Mountain Railroad
BTMRR - Big Thunder Mountain Railroad
BW - Disney's BoardWalk
BWI - Disney's BoardWalk Inn
BWV - Disney's BoardWalk Villas [a DVC Resort]

CB - Character Breakfast [Breakfasts where Disney Characters show up.]
CBJ - Country Bear Jamboree
CBR - Disney's Caribbean Beach Resort
CG - California Grill
CM - Cast Member [An employee of the Walt Disney Company]
Cont - Disney's Contemporary Resort
CoP - Walt Disney's Carousel of Progress
CP - Candlelight Processional
CP - Crystal Palace
CRO - Central Reservations Office [handling Dining and Resort reservations]
CS or CSR - Disney's Coronado Springs Resort
CS - Counter Service meal [part of Disney Dining Plan]
CW - Comedy Warehouse at Pleasure Island

D/MGM - Disney-MGM Studios

DAKL - Disney's Animal Kingdom Lodge

DCA - Disney's California Adventure
DCL - Disney Cruise Line
DD - Downtown Disney
DD - Disney Dollars
DDE - Disney Dining Experience [discount card available to FL residents & Annual Passholders]
DDP - Disney Dining Plan
DHS - Disney's Hollywood Studios (formerly Disney-MGM Studios)
DL - Disneyland
DLH - Disneyland Hotel
DLP - Disneyland Paris
DLR- Disneyland Resort
DME - Disney's Magical Express
DQ - Disney Quest
DTD - Downtown Disney
DRC - Disney Reservations Center [handling Dining and Resort reservations]
DVC - Disney Vacation Club
DW - Walt Disney World Resort
DWWS - Disney's Wide World of Sports

EC - Epcot
ECV - Electric Convenience Vehicle (electric wheelchair/scooter)
EE - Expedition Everest
ELP - Main Street Electrical Parade (electrical parade)
EMH - Extra Magic Hours
EWP - Electrical Water Pagent
ExE - Expedition Everest

FF - Flying Fish
FoTLK - Festival of the Lion King (Animal Kingdom)
FP - Fast Pass
FtW - Fort Wilderness
FW - Disney's Fort Wilderness Campground
FW - Future World (part of Epcot)

GF - Disney's Grand Floridian Resort and Spa
GMR - The Great Movie Ride
GN - Grad Night
GoH - Guest of Honor [written as GoH '76 meaning the first year you visited WDW]
GR - Guest Relations [at theme parks and Downtown Disney]
GS - Guest Services [at water parks]

HDD- Hoop De Doo Review (Fort Wilderness Campground) sometimes seen as HDDR
HH - Disney's Hilton Head Resort [a DVC Resort]
HISTA - Honey, I Shrunk the Audience
HM - The Haunted Mansion
HM - Hidden Mickey
HoP - The Hall of Presidents

IASW - "It's A Small World"
IG - International Gateway
IN - IllumiNations
ITTBAB - It's Tough To Be A Bug (at Animal Kingdom)

JC - Jungle Cruise
JIYI - Journey Into Your Imagination

KRR - Kali River Rapids
KJS - Kilimanjaro Safari
KTTW - Key To The World card [your Disney resort ID card]

LBV - Lake Buena Vista
LC - Lobby Concierge [the former Guest Services at the resorts]
LMA - Lights, Motors, Action! Extreme Stunt Show
LS - The Living Seas
LTT - Liberty Tree Tavern

ME - Magical Express
MGM - Disney-MGM Studios
MILFCC - Monster's Inc. Laugh Floor Comedy Club
MK - Magic Kingdom
MNSSHP - Mickey's Not-So-Scary Halloween Party
MS - Main Street USA
MS or M:S - Mission:SPACE
MSEP - Main Street Electrical Parade
MV3D - Muppet*Vision 3D
MVMCP - Mickey's Very Merry Christmas Party
MYW - Magic Your Way tickets and/or packages

NE - No Expiration [added to Magic Your Way tickets]
NoJ - Night of Joy
NOS - New Orleans Square

OKW - Disney's Old Key West Vacation Club Resort
OPR - Old Port Royale (at Disney's Caribbean Beach Resort)

PAP - Premium Annual Pass
PC - Pop Century Resort
PH - Park Hopper [ticket add-on to Magic Your Way tickets]
PH - Planet Hollywood (part of Downtown Disney)
PI - Pleasure Island (part of Downtown Disney)
PO - Disney's Port Orleans Resort, now Port Orleans French Quarter
PoC - Pirates of the Caribbean
POFQ - Port Orleans French Quarter
Poly - Disney's Polynesian Resort
POP - Pop Century Resort
PORS - Port Orleans Riverside (formerly Dixie Landings)
PotC - Pirates of the Caribbean
PPP - Pirate and Princess Party

RC - Rainforest Cafe
RnRC - Rock 'n' Roller Coaster
RS - Port Orleans Riverside (formerly Dixie Landings)

SB - Stormalong Bay [pool at Yacht & Beach Club]
SE - Spaceship Earth
SGE - Stitch's Great Adventure
SM - Splash Mountain
SM - Space Mountain
SoG - Shades of Green Resort
SP - Seasonal Pass [available only to Florida residents]
SplM - Splash Mountain
SSE - Spaceship Earth
SSR - Disney's Saratoga Springs Resort [a DVC Resort]
ST - Star Tours
ST - Disney-MGM Studios
SWW - Star Wars Weekend

TDS - The Disney Store(s)
TL - Typhoon Lagoon
ToT - "The Twilight Zone Tower of Terror"
TS - Table Service meal [part of Disney Dining Plan]
TSI - Tom Sawyer Island
TT - Test Track
TTA - Tomorrowland Transit Authority
TTC - Transportation and Ticket Center

UoE - Universe of Energy

V&A - Victoria & Albert's
VB - Disney's Vero Beach Resort [a DVC Resort]
VotLM - Voyage of the Little Mermaid
VWL - Disney's Villas of Wilderness Lodge [a DVC Resort]

WDTC - Walt Disney Travel Company [handling Dining and Resort reservations]
WDW - Walt Disney World Resort
WL - Disney's Wilderness Lodge Resort

WLV - Villas at Wilderness Lodge

WoD - Disney's World of Disney
WoL - Wonders of Life
WPF&M - Water Park Fun & More [add-on to Magic Your Way tickets]
WS - World Showcase (part of Epcot)

WS - West Side (part of Downtown Disney)
WWoS - Disney's Wide World of Sports
WWS - Disney's Wide World of Sports

Y&B - Disney's Yacht Club Resort and Disney's Beach Club Resort
YC - Disney's Yacht Club Resort

Other common abbreviations used on the Internet
(this list doesn't have *all* the abbreviations)

AFAIK - As far as I know
AYR - As you recall
BTW - By The Way
FWIW - For what it's worth
GMTA - Great minds think alike
IIRC - If I recall correctly
IME - In my experience
IMHO - In my humble opinion
IYKWIM - If you know what I mean
J/K - Just kidding
JMHO - Just my humble opinion
OT - Off topic
OTOH - On the Other Hand

ROFL - rolling on floor laughing
ROFLMAO - rolling on floor laughing my *butt* off
TIA - Thanks in advance
TMI - Too much information
TTFN - Ta Ta For Now
TTYL - Talk To You Later
YMMV - Your Mileage May Vary (means that no two people experience the same thing in exactly the same way, just a caution placed on some descriptions of places, events, food, merchandise, consumer habits, practices, etc.)

Common abbreviations for relatives

BF - Boyfriend
BIL - Brother-in-law
DBF - Dear Boyfriend
DBIL - Dear Brother-in-law
DD - Dear Daughter
DF - Dear Fiance
DFIL - Dear Father-in-law
DGF - Dear Girlfriend
DGF - Dear Grandfather
DGM - Dear Grandmother
DH - Dear Husband
DMIL - Dear Mother-in-law
DS - Dear Son
DSIL - Dear Sister-in-law
DW - Dear Wife
FIL - Father-in-law
GF - Girlfriend
GF - Grandfather
GM - Grandmother
MIL - Mother-in-law
SIL - Sister-in-law
SO - Significant Other

A Couple of Notes

Emoticons - Emoticons: Punctuation signs that are arranged within text in such a way as to display the simulation of a face when viewed by turning your head to one side. Inserted into text to relay a facial expression or emotion/attitude to match the text, softens the text to "humanize" it somewhat and make it seem less harsh, less blunt, offered as friendly advice, etc., or to relay how news/information affects the writer.

:-) or :) - Happy/smiling
:-( or :-( - Sad/frowning/disappointment
:-D - Very happy/Very big grin
:-/ - Skepticism/not feeling great
;-) or ;) - Winking and smiling/in-joke or joking or teasing
:-| - Ambivalence/Not pleased

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