acid trip

slang An intense hallucinatory experience as a result of ingesting lysergic acid diethylamide (LSD), commonly known as "acid." I had a really bad acid trip once. I thought I was being chased by man-eating monkeys through a forest made of chocolate! The film's visuals call to mind a prolonged acid trip, a twisted version of reality where strange things are possible. Do you need to be on an acid trip to understand this book? What does it all mean?