Here is a glossary for words and abbreviations you might see on chat or on various pages of the game.
FAQ: Frequently Asked Questions - answers to the most common game questions, found by going to the green question mark in the upper left hand corner of your screen. (hint: you are there now)
Barn: Place where riders add XP to horses.
Arena: Place where trainers train horses and players to do better in shows.
Arena Trainer: Player who belongs to the Trainer guild. Stable: Place you keep your horses.
XP: eXperience Points, what your player and horse need to advance through the levels.
Home Page: Page where you find your ranch and player stats.
Partner: Person that helps with your horses, ranch, tack, etc. You are allowed 2 partners at a time.
Mod: Short for Moderator. They are hand picked by Gatekeeper to enforce game rules and to keep the game moving smoothly.
K or k: When seen after a number, it means thousand. 5k is 5000, 100k is 100000
mil: When seen after a number, it means million. 1mil is 1000000
Blog: journal for your notes and thoughts. (Please keep them appropriate, they will be deleted if they are not)
Layout: HTML coding that creates a unique page for your player
HTML: codes that web pages turn into pictures and words on your screen.

Pro Pics: Picture for a horse, layout, or player.
Spam: Silly Pointless Annoying Messages. Posting more than two smilies per line, no words but only smilies, random letters such as asdlkfjewiofds, or repeating letters like hahahahahahahahahahahahahahahah or lolololololololololololololol on the chat lines is considered spam. Spam is not tolerated on the chat, and you will probably be muted by a mod.
Mute/muted: A mod has put you on "time out" for breaking game rules, and you can not type on the lines until you are unmuted.
tell: private message sent via chat
Banned: Your game playing abilities have been removed because you broke the rules. You will not be allowed to play until you are unbanned or your ban is lifted.
LOL: laughing out loud
BRB: be right back
IDK: I don't know
BBL: Be back later
TTYL: Talk to you later

Tack: Saddle, bridle, horseshoes, saddle pad, horseboots.
FIB: Flattened Iron Bar - used for making horseshoes.
Show Training: Entering a horse in shows.
Show Trainer: Person you pay to enter your horse in shows.
Pages: Number of site pages of shows a horse has available to enter. There are 25 shows per page.
Spec: Specialty or Specialization, also known as discipline meaning type of show or tack such as dressage, racing, western, etc.
Stats: Horse or player information, often includes disciplines, bonuses, skills, percentages, pedigree, and happiness.
Pedigree: parents, grandparents, etc.
Vetting: To take a horse to get shots and checkups, or to do vet work in the services area
Stablehand: Person who has a job feeding, treating, and grooming horses, also feeds market horses.
TB or tb: Short for Thoroughbred, a breed of horse.
Hano: Short for Hanoverian, a breed of horse.
AQH: American Quarter Horse
TWH: Tennessee Walking Horse
SEA: Straight Egyptian Arabian