a few the above posters (good job) somehow missed:

3 = from the LGA "3-1-1" mantra, a unit of measure equal to 3.4 ounces. Origins of "3.0 = 3.4" are sketchy, but may derive from the "2 + 2 = 5" in the DHS organizational manual, 1984.

KST = Kabuki Security Theatre = after the Japanese stylized theatre, i.e TSA checkpoint modus operandi, where an impressive display of bluff, barking, blue shirts and badges impresses the he!! out of infrequent flyers, known as Ma and Pa Kettle and/or Sheeple, to the point they predictably say "well, I guess, anything for security" when a reporter shoves a microphone in their face as they wait in the 1 hour checkpoint line in Concourse C for the TDC to shine his UV on their ID.

UV = Ultra Violet = Blacklight = Magic flashlight = a handheld device for the Government make work program to employ TDCs, who shine it on 2 million IDs per day to make sure none contain the invisible secret phrase "This passenger is really Osama Bin Laden in disguise". Sucess rate to date = 100%.

OBL = Osama Bin Laden = and excuse for Bush/Cheney/DHS to trample any right listed in the US Constitution, in public or in secret, often in a sentence containing a variation of "well, you know, it's a different world we live in, post 9/11".

9/11 = see OBL, same definition.

KGB = variations STASI, SS, Gestapo = totalitarian secret police organizations existing prior to the DHS. The underground thumping sound you hear is Stalin and Himmler rolling over in their graves, kicking and screaming over their misfortune to come along 50 years too early, for if only they had the computer power of DHS you would be reading this in German or Russian.

RMA = Respect Ma Authoratay = Power tripping atitude by persons given more power than they can handle. Commonly displayed by the same TSO one stripers (see definition) who utter D-Y-W-T-F-T? (see definition).

H2O = Dihydrogen Monoxide, the most powerful high explosive on earth according to Nobel Prize for Khemistry Winner Kip Hawley, of KHIAI fame. Can be made more powerful with the addition of best selling orange flavored powdered breakfast beverages, not to be confused with the grape-flavored powdered Flavor Aid beverage which Kip and his loyal followers are fond of.

FB = Freedom Baggie AKA Kip Zips, Kip Quart Baggie, Kip Kwarts, after the "KH" of KHIAI AKA Kip or The Kipster = a one quart zip top plastic bag made by the S. C. Johnson Company, having the magical powers of rendering 3.4 ounces or less quantities of high explosive water into ordinary water as long as the zip top is securely closed.

NIT = Not an International Terrorist = DHS/TSA employees.

SIT = Suspected International Terrorist = every other citizen of planet Earth who is not a DHS/TSA employee.

ID = Identification = easily forgeable documents which "KH" of KHIAI somehow equates with security.

NFL = No Fly List, a List which cannot be properly be publicly defined, as the Flyertalk word censors and TOS prevent an accurate description, even in OMNI.

SSI = something so secret even HSVTSO Dean had to leave it off his list.