Not sure the term disease really is inaccurate

Disease: a disordered or incorrectly functioning organ, part, structure, or system of the body resulting from the effect of genetic or developmental errors, infection, poisons, nutritional deficiency or imbalance, toxicity, or unfavorable environmental factors; illness; sickness; ailment.

Though I understand when most people hear 'disease' they think of like a sickness or virus so the thought of mentally ill being 'diseased' can have negative connotations due to that. So with all that said I do prefer the term disorder as well, even though technically 'disorder' falls under 'disease'.

As for depression I wonder, should it be called depression?....I mean many people take it to just mean 'sad' so then they don't take the disorder seriously. I admit I do not have a better name for it at this point...I know one correct name is Major Depressive Disorder, though I have heard that referred to as Major Depression, Clinical Depression, Chronic Depression ect. I guess one thing to keep in mind is if someone says they are 'depressed' that does not necessarily mean they are suffering from a depressive disorder, but it can sometimes be hard to tell what is meant.