The most powerful strain of marajuana ever concieved. It in fact is no myth, only in the aspect of it being "pure".It was part of a government research project done between the 1970s and 80s and the only reason it can be found on the streets today is because it leaked, but it was only a clone that made it out of the government labs and into the world, so it can only be crossbread in order to be reproduced. The most potent crossbread samples ever tested were found to have an amount of about 18-19% THC by weight(this is amazing!!!!). Its name has many rumors for the origin of it. For Example: G(Government)-13("M" 13th letter of the alphabet, for Marajuana), G(Grow room)-13. All other rumors for the name's origin are question to too much speculation, and therefore are not taken into account. It is of Afghani or "Indica" origin, but not an incredible amalgamation of many(It's true genetics are not known to me, and I dont think anyone else).
by zig-zag man March 8, 2007
The dankest pot ever made. It was made by the government. A plant was stolen once and spliced with another strain, that is the closest potency you can get to g-13.
by me March 25, 2003
g-> Goverment, 13> m the 13'th letter in the alphabet which is short for maryjane, also know as mr. nice
by flynigger February 8, 2004
by kain April 6, 2003
a strain of marijuana engineered by the u.s. millitary. it is a combination of over 200 different strains from around the world. it gets its legendary name from its 13% THC content
by god October 13, 2003