A gathering of nerds attempting social contact, likely for the first time. Usually disintegrates into everyone running to the nearest computer to type to one another.
Tommy: Hey Jethro, quit playing WoW its time to meet some folks at the tweetup!
Jethro: Oh yeah I forgot about that, I can't wait to meet BigBootay421 at the tweetup, but first I need to slay this orc!
1. A person who is unable or unwilling to be shown how to tweet on Twitter. Most often a technologically challenged individual, usually associated with advanced age.
2. The complete fear of Twitter or anything associated with it.
Teen: My dad is such a tweetaphobic! He doesn't even have a cell phone!!!! HE IS SO 50's!!!!!
To cram a "tweet" on Twitter in Twitter's 140 character limit using an intense level of chat-speak ; a hybrid between the terms "chat-speak" and "tweet."