Abbreviations

There are many abbreviations used colloquially in lolita fashion, may of which you will find listed below:

A-D

AatP - Alice and the Pirates
AP - Angelic Pretty, rarely Alice and the Pirates or Atelier Pierrot
AtePie - Atelier Pierrot
AtPie - Atelier Pierrot
BtSSB - Baby, the Stars Shine Bright
BPN - Black Peace Now
CDC - Crystal Dream Carnival, a popular print by Angelic Pretty
CGL - Cosplay & EGL; refers to a 4chan board popular in the early 2010s for discussion of lolita fashion (see more)
Concrit - "Constructive criticism". Often referred to in coord-sharing spaces, social media and forums, referring to advice or suggestions on improving an outfit or piece.
DD - Dream Dress. A specific wanted piece that is difficult to obtain which someone spends, sometimes years, saving for or trying to find for sale.
DDC - Day Dream Carnival, a popular print by Angelic Pretty
DA - Direct Auction (carried over from the old livejournal sales platform)
DS - Direct Sale (carried over from the old livejournal sales platform)
DT - Direct Trade, a one-to-one trade (carried over from the old livejournal sales platform)

EGL - Elegant Gothic Lolita, a term created / popularized by Moi-Meme-Moitie. Alternatively, the Livejournal group of the same name.
ETC - Emily Temple Cute
GLB - Gothic & Lolita Bible, a Japanese magazine featuring gothic and lolita fashion brands and updates.
IG - Iron Gate, a popular print by Moi-Meme-Moitie.
IW - Innocent World
JetJ - Juliette et Justine
JSK - Jumper Skirt, a dress without sleeves (see more)
KC - Short for the Katyusha, the Japanese word used for head bow
LBS - Little Bunny Strawberry, a print by Angelic pretty
LM - Lace Market, an online sales site
MAM - Not actually intended as an abbreviation, but the name of a sweet-lolita Maxicimam sub-line, occasionally used interchangeably with the brand in conversation.
Meta - Metamorphose Temps de Fille
MM - Mary Magdalene
MMM (sometimes MmM)- Moi-Meme-Moitie
MTO - Made to Order. Brands will occasionally do an MTO of a release by opening preorders for an item rather than releasing a set amount of stock. These can be either set sizing or custom-sized depending on the brand and release.

NOP - No Sleeve OP, aka a JSK, used primarily by Emily Temple Cute
OP - Onepiece, a dress with sleeves (see more)
OTKs - Over the Knee Socks (see more).
OTT - Over the top: refers to outfits that really go "all out" within a substyle and frequently make use of many or very bold accessories.
PtMY - Not actually intended as an abbreviation, but the name of a Putumayo sub-line targeted towards a more masculine aesthetic.
SK - Sometimes used as an abbreviation for Skirt
SS - Shopping Service, a proxy buying service used to purchase overseas items which may or may not offer international purchases/shipping. Typically purchases, consolidates and forwards parcels, though this term can be used colloquially to indicate both full shopping services and forwarding services, which simply fforward domestic parcels internationally. Used often for Taobao shopping as well as first and second-hand Japanese shopping. (see more)
TPS - Tea Party Shoes, a style of shoes designed by Angelic Pretty and frequently re-released. Sometimes includes fakes and shoes that look vaguely like AP's shoes.
RHS - Rocking Horse Shoes, a shoe style made by Vivienne Westwood
VM - Victorian Maiden
VW - Vivienne Westwood
WTB - Want to Buy (carried over from the old livejournal sales platform)
WTT - Want to Trade (carried over from the old livejournal sales platform)
Y!JA - Yahoo!Japan Auctions, a popular secondhand Japanese sales platform on which lolita items may often be found.