Psychosomatic is actually an interesting one -- it's not just "lazy doctors" -- there's plenty of evidence to show that the brain is totally capable of causing a range of side effects all on its own (Placebo and nocebo trials have made this clear).
If you want annoying go for "Idiopathic". For example I have idiopathic optic nerve hypoplasia. The last three words mean my optic nerve is narrow than it should be - I have a gap in one quadrant of my peripheral vision - the "idiopathic" bit means they don't know why.
I agree with you, but if there is no evidence that something is psychosomatic, the doctor shouldn't give the diagnosis that it is. If a doctor is keen on dismissing the patients I think that should be investigated and that person barred from working in the field.
