Pansexual was first used in psychology to refer to the idea that sex is the primary driver of all human behavior, pan-here from the Greek meaning “all.”. The word was originally leveled against the ideas of Sigmund Freud as far back as 1914. Critics were still arguing against this supposed pansexual psychology in the 1950s and 1960s. New meanings for pansexual emerged in the 1960–70s.

