Aegyo - cute actions.
Aigoo - "Oh no" or "Oh dear". Its mostly used by older Koreans.
Ahjumma - older female.
Ahjusshi - older male.
Antis - people who aren't fams and go out of their way to criticize and attack the artists they don't like.
Babo - fool.
Bias - who you like the most.
Byungtae - pervert/perverted.
Chingu - friend.
Chocolate abs - really defined abs.
Comeback - when an idol group comes out witha new song after a hiatus.
Debut - when a new idol group comes out.
Eye Smile - when the eyes of the celebrity forms the shape of a smile as they actually smile.
Fanchants - chants fans say. Scream out during live performances for support.
Fandom - fanclub.
Fanwars - when fans of an idol group are fighting against fans of another group.
Flower Boy - a very attractive guy who has slightly feminine features.
Hallyu Wave - the spread of Korean Music outside of Korea.
Hwaiting - encouragement or "Good Luck."
Hyung - what a male calls an older male as respect.
Jjang - "the best!"
Kamsahamnida - "thank you."
Maknae - the youngest member of the group.
MV - Music Video.
Netizens - members of the internet and forum communities.
Noona - used by males to refer to older females/sisters.
Oppa - brother, used by woman to call an older male.
Sarang/Saranghae/Saranghaeyo - Love or I Love You.
Sasaengs/Sassaengs - crazy stalker posing as fans.
Selca - self taken picture.
Stans - fans who are loyal.
Ulzzang - best face.
Unnie - term used by female to refer to older females/sisters.