A stupid 'specialist' to whom S was referred when we were applying for ill-health retirement stated in an illiterate report that she appeared 'not so much demented as depressed' - this when she had already been attending the memory clinic for several years and when regular tests and several scans had shown that there was a real problem. No-one else felt that, at that time, she was depressed in a clinical sense though naturally she wasn't over the moon about what was happening to her.
This is not some PC thing. The words just aren't helpful - to anyone.
Connected to this is the whole concept of diagnosis, of which more later.