I agree completely. I've had several points when I'm describing a character as displaying the symptoms of Depression, and my adviser will comment are you saying they display the symptoms of clinical depression/MDD. TO this, I try to revise so it is obvious that I believe the character displays traits readers may identify as the character having a clinical issue, or Depression. My thesis, after all, is on using YA speculative literature about mental illness as bibliotherapy. The clinical is of much greater interest to me.

Personally, depression and Depression tend to blend together thanks to a Heinz 57 mix of different mental illnesses. When I see it in others, I try to read the situation and be supportive regardless of whether or not I can ascertain which is going on. Telling someone to just pull themselves up by their bootstraps is offensive even if it is just depression. I'd rather just be their friend.

Overall, I do believe this is one of the points in which the English language has failed us in terms of ambiguity.