When I first finished my science degree I was working as a medical technologist. That was what I'd put on my tax forms. A few years later, I was still doing the same job but was then classified a hospital scientist, and a few years further on I was a medical laboratory scientist, which is how I still think of the profession, and the title I prefer. A technologist is different to a technician, by the way, because a technologist does diagnoses and is more highly qualified. But many people (including those in ancillary fields) didn't recognise this difference, and I suspect that's why the qualification first changed its name. It's all about snobbery! I do, however, think "medical laboratory scientist" is a good descriptor: we were working in the medical field (usually attached to a hospital, but I did work in one private practice that wasn't) in a lab as a scientist. Perfect.
I'm no longer working in the field, so it could be that I'd have a completely different name now. (And, you know, when we graduated the whole class graduated as having a Bachelor of Applied Science in Medical Technology except for one student who'd already hopped onto the Medical Scientist label. That was rather odd.)
In that time I worked as a microbiologist and a haematologist, but as a scientist, rather than a doctor. For the uninitiated, it's all very confusing. So the haematologist you have a consultation with in a big public hospital is going to be a doctor, not a scientist. The scientist-haematologist is the one who'll do your blood work up, who'll look at your blood film and tell the doctor what's wrong. Both are called haematologists.
Now I'm a teacher, I don't find the terminology is any better: I can be labelled a teacher, a tutor, a lecturer (though I tend to think of this as more a Higher Ed than TAFE thing) and, now we're teaching online units, a facilitator. I probably like the term "facilitator" the least, as to me it seems to have little to do with "teaching" per se. I think it pays more homage to collaborative learning, though, which is a technique we do use a lot in the classroom through workshopping, and I have to say I'm a great believer in collaborative learning. But we still do "teach" -- it's what the students want, what they recognise us as. We facilitate as well, but we do more than this.
Even in writing there is the difference between a "writer" and an "author". (Or authoress, as my mother seems determined to say. I point out that this term is now considered sexist, and she tells me that I'm out of my mind. I could talk about the linguistic distinctions, and how the suffix is dependent on the male word to determine its meaning, but her eyes would glaze over. Such things excite me, though. It's the editor in me!)
We had great discussions about the difference between a "writer" and an "author" in my online course. I see the two as completely interchangeable. But for others an author was more serious, or was published, or had a book or number of books published. To me, the distinction is once again a snobbish thing. A writer writes. Does an author auth? If you've written an unpublished and unpublishable short story, aren't you still the author?
Me: I'll go for "writer". I think I'll always prefer the plainer, more simple descriptor.