Permanently experiencing the effects of or suffering permanent psychological damage as a result of prolonged or intense use of psychoactive drugs. Sometimes written as one word. Someone spiked David's drink with nearly 20 doses' worth of acid, and the poor guy has been perma-fried ever since. I just don't think you can get permafried from smoking weed. You might turn into a loser if you smoke it all the time, but you're not going to permanently screw up your brain or anything.