PC = Peace Corps, but you could probably figure that out. 

ID4 = Peace Corps Indonesia Group 4, consisting of 18 volunteers serving from 2010-2012. They were the first Peace Corps group to enter Indonesia since the 1960s when groups ID1, ID2, and ID3 served. 

ID5 = Peace Corps Indonesia Group 5, currently consisting of 20 volunteers serving from 2011-2013. This is my group.

ID6 = Peace Corps Indonesia Group 6, currently consisting of 42 volunteers serving from 2012-2014.
PCV = Peace Corps Volunteer - In training, I was not yet a PCV. I swore in as a PCV in June. 
PST = Pre Service Training - We went through 10 weeks of training consisting of language classes, teacher training, cultural sessions, safety and security training as well as medical info sessions. Oh, and lots of shots.
Village = I know you know what this is, but we trained in a community learning model where the 30 volunteers were split up into 6 villages to live and study. There were 2 other PCVs in my village – Jay and John. This was who I saw every day for language classes, teaching, playing Frisbee, running, and/or exchanging stories. We had 2 other PCVs, but our friends, Andria and DJ, unfortunately, returned home because Andria’s father is ill. We miss them and hope Andria’s dad is OK.
Link = A few times a week, we met up in Links where 3 villages came together for sessions on TEFL, safety, etc. There were 15 volunteers per link.
HUB = Hub days were days where all 30 volunteers came together at UMM campus for training, shots, exchanging music, movies, etc. We also got to make use of free internet at UMM as the tight schedule allowed.
IST = In-Service Training Roughly 6 months into service, we went to Surabaya for two weeks for shots, required safety and medical sessions, and TEFL training with our counterparts.

MST = Mid-Service Training Roughly mid-way through service, we will go through one week of training on developing community projects with a counterpart and maybe a dental cleaning!

RPCV = Returned Peace Corps Volunteer
COS  = Close of Service (end of 27 months of service)

ET = Early Termination so far out of 31 PCVs in our group, we have lost 5. We hope we don't lose any more!!!
Bule = white person in Indonesia
Dangdut = popular type of music in Indonesia. I am still learning, but so far, it sounds like a blend of house and pop with a dash of techno.
Gamelan =  again, still learning, but is a musical instrument with a sound of the xylaphone variety.  Very soothing.

Sunat = boys are circumcised at a later age (usually 10-12 in these parts), and they have a big party thrown for them. I have attended several of these which are similar to weddings with music, food, and the poor little guy just sits there all dressed up. 

RamadanRamadan is the ninth month of the Islamic calendar marked with fasting from food, drink, and sexual activity during the daylight hours for the entire month. In Indonesia, Muslims wake up to eat/drink from 3-4am and then they do not eat again until Maghrib at around 5:30pm. In addition to fasting, focus is placed on helping others and cleansing spiritually by not telling lies, gossiping, arguing or being greedy. Everyone who celebrates Ramadan is asked to do as many good deeds as they possibly can over the course of the holiday.
Bejoso = The training village of Beji, consisting of three remaining PCVs, sought a merger with the three remaining members of Rejoding (already a combination of the Rejoso and Jeding training village names) to form a new force, known as Bejoso. Terms of the merger were agreed upon effective August 11, 2011. 

I apologize in advance for not having this alphabetized.