Someone who has not just done too much acid, but way too much acid over a period of time. The result: "weird" behavior and thought processes - an unhealthy obsession with black helicopters, for instance, or the desire to hitchhike, barefoot, from Ottawa to Winnipeg in search of Uncle Luigi, who died five years ago. The Guru Boom of the mid-to-late-60's may have been populated by a large number of acid casualties; many became devotees, a few even were self-styled gurus.