Well, look here and find the answer to those questions!
2AM (I Am): 2PM + 2AM = One Day. Put the two names together and you get “I Am Hottest”
2PM (Hottest): JYP considers 2:00 PM as the hottest time of day.
2NE1 (Blackjacks): 21 is the highest number a person can achieve while playing Blackjack.
4Minute (4Nia): 4Minute Mania.
After School (Play Girlz): Pledis asked fans to give suggestions. Play Girlz was the name chosen and it’s the name of a track on their first mini album.
A Pink (Pink Panda): “Pink Panda” is a play on the name of the group and the Korean word for ‘fan’ (팬, paen).
B1A4 (BANA): ”BANA” refers to “BA (B1A4) NA (fans)”, and put together it means “we have fallen for each other (BANADA)!”.
B2ST (B2UTY): Beauty and the Beast.
Big Bang (VIP): VIP stands for “Very Important Person”. Their second single La La La is also referred to as Big Bang is VIP.
BoA (Jumping BoA): The idea that BoA’s lively and energetic music makes her fans dance and jump.
Boyfriend (Bestfriend): The same initials with BoyFriend; B.F! Just like the meaning of the name, Boyfriend’s members hope to deepen their relationship and care for each other.
Brown Eyed Girls (Everlasting): The four members that make up BEG are unified with their fans for everlasting.
CN Blue (Boice): A combination of “Blue” and “Voice”. FNC Music declares that CN Blue’s fans are their voice.
DBSK (Cassiopeia): The constellation Cassiopeia is made of five points that create a “W” in the sky. The group DBSK also uses the synonym TVXQ. Tracing TVXQ on a keyboard coincidentally makes a ‘W’. The Cassiopeia fanclub refers to themselves as Cassies for short.
Epik High (High Skool): High Skool is the name of a song off their album High Society.
FT Island (Primadonna): Named after the title of a song from their first studio album.
Girls’ Generation (S♥NE): When written in Hangul SONE is “소원”, which means “wish”, and was a song featured on their first album as well as in the title of their song Tell Me Your Wish. It also has a deeper meaning: “소원” (SoWun), pronounced “So One”, implies that Girls’ Generation will always be one with their fans.
Infinite (Inspirit): Woollim Entertainment held a poll and Inspirit received 70% of the vote.
Jay Park (Jaywalkers): Jay wanted his fans to choose the name. The fans submitted the names and it was narrowed down to three chosen by Jay. The fans chose Jaywalkers in the final poll.
Jewelry (Jewel Box): Jewelry is best kept safe and protected in a Jewel Box.
KARA (Kamilia): KARA‘s fans are like their family. Put KARA and the Spanish word “familia” together and you get Kamilia.
MBLAQ (A+): All the members of MBLAQ have the blood type A, and the “+” comes from Music Boys Live in Absolute Quality. The “Absolute Quality” is A+.
Miss A (Say A): The name was announced by Miss A via a video posted to their daum cafe in the hopes that fans will shout “Say A” at their performances.
Rain (The Cloud): Clouds carry and bring the rain.
Rainbow (Rain-nous): Rainbow + Luminous.
Se7en (Lucky Se7en): Se7en himself believes that his fans bring him luck. It also is a reference to seven as a lucky number.
SHINee (SHINee World): Named after their first studio album. SHINee fans also refer to themselves as Shawols. It’s a shortening of SHINee World (샤이니월드), SHYA and WOL = SHAWOLS.
Sistar (Star1): Starship Entertainment held a poll and STAR1 received the most number of votes. Additionally, if you combine the word “star” and the Korean word for one, you get STA(R) + IL = STYLE.
SS501 (Triple S): SS in SS501 stands for Super Star. The added “S” stands for Supporter.
Super Junior (Everlasting Friends AKA ELFs): This name is given to their fans who will always be their fans and love them no matter what. Also, it means that their fans are more than fans to them, they’re more like dear friends.
Teen Top (Angel): TOP Media held a poll and “Angel” received the most voted, along with multiple names such as “Top Planet” and “Andromeda”.
The BOSS/DGNA (Master): The meaning behind “Master” is The Boss’ owners who have mastered everything about them. It means the artiste and fans trust each other and stand by each other.
U-Kiss (Kiss Me): If U-Kiss were to ask “Who should I kiss?” the fans would reply “Kiss ME!”
Wonder Girls (Wonderful): Fans are “full of wonder” for the Wonder Girls.
ZE:A (ZE:A Style): ZE:A Style was one of ten contenders for a fan club name, and voting through their daum cafe revealed that ZE:A STYLE was the winner.