Want to know what that odd-sounding word means and why everybody but you seems to just "get it"? Or maybe you want to know who GM is and why mob keeps showing up. Or perhaps you're curious about where zerks are and why you can't seem to find anybody called GRD! Look here, this will help.

Short name	Full name	Description	Need more info? Check these pages
Aid / Tool / TA	Tool Aids	An item which shortens the time taken to gather materials.	Tool Aids
Acc	Accessory	Stat-boosting item that you can wear.	Accessory guide
AFK	Away From Keyboard	Indicates that the player is away from the computer.
Aggro	Aggressive	Type of monster behavior. Aggressive monsters attack when you get close to them.
Aggro-aided	Protective	Type of monster behavior. Protective monsters gang up on you when you attack any one of them.
AoE	Area of Effect	Type of skill/attack that hits more than one target.
GGD	Grand Golden Dragon	Level 95 Boss Raid monster on the Egeha map.	Boss Raid monsters and unique accessories
Boosters	Skill Point / Experience Boosters	Gives 4x skill point experience or experience for the next kill.	XP boosters / SP boosters
bx	Blue Sealed Equipment	Level 73+ equipment that is blue and has x seals.	73+ weapon seals
CB	Chaos Ball	Event item given to Estella for a reward.
Char	Character	Refers to a player or players.
CoR	Crest of Rainbow	Rare accessory.	Boss Raid monsters and unique accessories
CoT	Chain of Tiger	Rare accessory.	Boss Raid monsters and unique accessories
CS / MCS	Merac Castle Siege	A guild event which takes place in Merac.	Merac Castle Siege
CSS	Chaos Smelting Stone	Type of smelting stone with a 100% chance of success up to +12.	Smelts and upgrading
Cerb(s) / Cereb(s)	Cerebrii	A level 51 Mob on the Merac Map.	Merac monsters
DCS	Dratan Castle Siege	A guild event which takes place in Dratan.	Dratan Castle Siege
Demon	Boucu Demon	Level 84 monster on the Egeha map.	Egeha monsters
DK	Death Knight of Iris	Level 52 boss monster found on level 5 (Torture Room) of Maargadum Jail, which is the public dungeon on the Merac map.	Maargadum Jail monsters
Dualclass / Class / Subclass	Character job option	Refers to a character's job opt
Duals/Twins	Twinblades	Two-handed swords for the knight class.
Ele / Elem	Elementalist	Sorcerer job option.	Sorcerer job options
EoW	Eye of Wiseman	Rare accessory.	Boss Raid monsters and unique accessories
ES	Extreme Stone	Type of smelting stone with 100% chance of success. Can only be used once on an item.	Smelts and upgrading
fl or FL	Friends List	In-game friends list.	Friend's list
gx	green sealed equipment	73+ equipment with a green name and x seals.	73+ weapon seals
G/ Gold	Gold coins	Basic unit of money (usually just called "gold").
GA	Guild Advisor	Member of a guild who can add other members.	Guild titles/positions
Kamira/Kami/GDK	Grand Devilroad Kamira	Level 70 Boss Raid monster on the Dratan map.	Boss Raid monsters and unique accessories
GGD/Bob	Grand Golden Dragon	Level 95 Boss Raid monster on the Egeha map. Sometimes also known as "Bob."	Boss Raid monsters and unique accessories
GHB	Great Horn Beast	Level 24 monster on the Juno map.	Juno monsters
GL	Giant Larvas	Dratan creature.	Dratan monsters
GL / GM	Guild Leader/Master	Leader of a guild.	Guild titles/positions
GM	Game Master	Aeria employee, "god" of the game.
GRD	Grand Red Dragon	Level 50 Boss Raid monster on the Merac map, also known as "skippy."	Boss Raid monsters and unique accessories
GS	Game Sage	Community volunteer who patrols the game.
Ghosts	Cursed Weaver, Cursed Lich	Nickname used to talk about level 88 Cursed Weavers and level 90 Cursed Liches, which are monsters on the Egeha map.	Egeha monsters
HB / hb	Horse buffs	Buff skills of a Knightmare (mounted horse).	Mounted pet skills
HH / hh	Happy Hour	A weekly event.
HL	Highlander	Titan job option.	Titan job options
HL	Highlander	Level 40 monster on the Merac map.	Merac monsters
HS	Heaven Stone	Type of smelting stone with a 50% chance of success, 16.6% chance of no-change, 16.6% chance of failure, and 16.6% chance of degrading.	Smelts and upgrading
IDB	Item Drop Booster	Item that gives a 30% greater chance of receiving a drop.
Illy	Iludeteirun	Level 105 boss monster found on floor 10 of Lust Trum, which is the public dungeon on the Egeha map.	Lust Trum monsters
Inki	Endemic Demon	Level 86 boss monster found on the Egeha map. Formerly called "Inkitomi", hence the nickname "Inki".	Egeha monsters
Iris	Blessed Iris	Increased EXP gain of +100% for three hours.	XP boosters
Jail	Maargadum Jail	Merac's public dungeon.	Maargadum Jail map
K (for example, 3k)	thousand (so 3k = 3,000)	Abreviation generaly used to talk about money, for example, 1k means 1,000 gold and 3kk means 3 million gold.
Kandant	Kandant Castle	Area in Merac where the Merac Castle Siege takes place.	Merac Castle Siege
KoS	Kill On Sight	A Term used by guilds, if they place a KoS or 'Kill on Sight' on you. Everytime a member from that guild see you they will attempt to kill you.
Koy	Ape	Level 74 boss monster found on the Egeha map. Formerly called "Koyemsi", hence the nickname "Koy".	Egeha monsters
KS/KSing	Kill stealing	Term used when someone is attacking a monster that someone else already starts attacking it too without the permission of the first, trying to "steal" their "kill" (which translates to looting rights).
LMAO	laughing my **** off	Used to show that something is really funny. The third word of the phrase is censored in-game.
LOL	laughing out loud	Used to show that you think something is funny or worth laughing at.
LSS	Lucky Smelting Stone	Type of smelting stone with a 100% chance of success up to +6.	Smelts and upgrading
Master	Master [class type]	The NPC that teaches skills to characters of your class type.
MC	Monster Combo Master Coin	Monster Combo - At Master of Monster Combo in Dratan. Master Coin - A coin received as a reward for completing Monster Combo	Monster Combo
Memo Scrolls	Scrolls of Memorization	Scrolls to teleport you to a saved location on the same map.
Merc	Merac	One of the five main maps.	Merac map
Merch	Merchant Mode	To go into merchant mode to sell items	Merchant Mode Guide
Mil (also called "kk")	million ( so 1mil = 1,000,000)	Abbreviation used to talk about money, 1mil means 1million gold (1,000,000 gold).
Min	mineral	Refers to minerals.	Powders
Mob	monster(s)	A monster or a group of monsters (depends on context).
Mod	Moderator	Community volunteer, patrols the forum.
Mount	Mounted pet	A pet horse (Knightmare) or drake (Dragon) that you can ride.	Mount training
MS	Moon Statue	NPC statue in Randol City, Juno where you may use Moon Stones to win prizes.	Moonstatue
MS	Moon Stone/Moon Statue	Used to play the Moon Statue "slot machine" in Randol City, Juno.	Moonstatue
Newb	Newbie	A newbie is someone considered as a relatively new person to a game that is inexperienced and doesn't know what they are doing. Not to be confused with Noob.	Wikipedia - Noob & Newb
Noob	Noob	A noob is generally a jerk, an idiot. Not to be confused with Newb. Most of people use Noob as the word Newb, but it's not the same thing.	Wikipedia - Noob & Newb
OoL	Origin of Land	Rare accessory.	Boss Raid monsters and unique accessories
Pilf	Pilferer	Level 33 monster on the Merac map.	Merac monsters
PK	player kill	The act of killing another player.	PvP & colored names
PKer	player killer	Someone with a red-colored name.	PvP & colored names
PKKer	player killer killer	Someone with a blue-colored name.	PvP & colored names
PL	Party Leader	In charge of a party.	Partying
PLvl	Power Leveling	Killing monsters too high for you, causing you to level quickly
Pnoob/Pnub	Power lvl noob	Power leveling with No or very few Skills maxed
Plat Iris/ PBI	Platinum Blessed Iris	Increased EXP gain of 300% for one hour.	XP boosters
Plat Super Skill Pill / PSSP	Platinum Super Skill Pill	Increased SXP gain of 300% for one hour.	SP boosters
PM	Private message	Message sent to another player in a way that only he or she can view it.
Pot	Potion	Refers to HP/MP potions and PvP remedies.
PoW / POW	Pierce of Wind	Rare accessory that boosts evasion.	Boss Raid monsters and unique accessories
Prok / Prokion	Prokion Shrine	Dratan's low level public dungeon.	Prokion Shrine map
PvE	Player versus Environment	Type of fighting in which a player is attacking a NPC (e.g. a monster).
PvM	Party versus Monster	Type of fighting in which a party is attacking a NPC (e.g. a monster).
PvP	Player versus Player	Type of fighting in which a player is attacking another player.	PvP & colored names
Pyra / Pyramid	Teo's Tomb	Temple in Dratan which contains level 100 and over monsters.	Tomb of Theos monsters
Q.Stones	Quality Stones	Heals a pet's hunger by 5 points.	Pet health, hunger, and sympathy
Rare	Unique Accessory	Type of accessory dropped only by Boss Raid monsters and the Shadow on the Strayana map.	Boss Raid monsters and unique accessories
Rc	Party Recall Card	An Item Mall card used to recall party members to the user's location.	Party recall scrolls
RK	Royal Knight	Knight job option.	Rogue job options
RoD	Rage of Demon	Rare accessory.	Boss Raid monsters and unique accessories
Sin/Assa	Assassin	Rogue job option.	Rogue job options
Skill / Stat Reset	Skill / Special Skill / Stat Reset Card	Item mall items that reset your skills / special skills / stat points. When resetting skills or special skills, all Skill Points are reclaimed for redistribution. Resetting your skills will also reset your job, so you will have to choose it again.
SoL	Stone of Life	Rare accessory.	Boss Raid monsters and unique accessories
Solo	Solo Party	Type of party. Or killing a monster without being in a party, Or any one helping.	Solo partying
Sonaba	Sonic Break	Former name of the Specialist general skill Sonic Break. It is still often used to reference the skill.	Specialist general skills
SoS	Stone of Shadows	Rare accessory that boosts evasion.	Boss Raid monsters and unique accessories
SP	Skill Point	Points required to gain or upgrade skills.	XP and SXP
SPB	Skill Point Booster	Booster that gives x4 Skill Experience Points for next kill (need to get last hit).	SP boosters
Spec	Specialist	Sorcerer job option.	Sorcerer job options
SS	Smelting Stone	Normal smelting stone with a 33% chance of success and 67% chance of failure.	Smelts and upgrading
Stray	Strayana	One of the five main maps.	Strayana map
SXP	Skill Experience	Type of experience required to gain Skill Points; earned by killing monsters.	XP and SXP
Tea / TT	Sunday Tea	Weekly event that takes place on Sundays.
TK	Templar	Knight job option.	Knight job options
ToK	Tear of Knight	Rare accessory.	Boss Raid monsters and unique accessories
Tomb	Tomb of Theos	Third public dungeon on the Dratan map. Contains level 100-110 monsters and is controlled by the guild that owns the Dratan pyramid.	Tomb of Theos monsters
Tower	Lust Trum	Egeha's public dungeon.	Lust Trum map
Velp	Velpist Temple	Juno's public dungeon.	Velpist Temple map
Wafes		Group of creatures.	Dratan monsters
Weap	Weapon	Type of equipment used to increase damage inflicted by attacks.
Wiz	Wizard	Mage job option.	Mage job options
WM	Warmaster	Titan job option.	Titan job options
WTB	Want To Buy	Somebody wants to buy an item.
WTS	Want To Sell	Somebody wants to sell an item.	How to sell
WTT	Want To Transfer	Somebody wants to trade their item for another.	How to trade
X-Bow	Crossbow	A ranged weapon for the rogue class.
XP	Experience	Points required to gain levels.	XP and SXP
Zerk / Zeker	Berserker	Level 34 monster on the Merac map.	Merac monsters
Zerk (-Potion)	Berseker Potion	ItemMall - Potion, 10% chance to get 2x Damage for one hit

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