1) The largest and arguably most informative drug website out there. Any substance the average person would come across in their travels, from Alcohol to Datura, is listed and explained by both scientific data and anedotes from other users.
2) It is also used as a verb in reference to this site.
1) Wow, I just checked out Erowid.org like you told me to, and now I know how to make LSA from Morning Glory seeds!
2) Person 1: Look at these mushrooms I picked this morning! Do you think they are psychedelic?
Person 2: Dude, I'm melting through the fucking floor... Go Erowid that shit