Every discipline has its own nomenclature—terminology that people outside that field sometimes find annoying. And no discipline multiplies the terminology like psychology. (I’ve always said that one key difference between philosophers and psychologists is that philosophers come up with new terms only when they are needed. That’s a joke…sort of.)
Check out this routine by George Carlin on the evolution of psychological terminology related to the condition formerly known as “shell shock.” Insightful at a number of levels.