Dogtrousers
Kilometre nibbler
Are all non-amateurs professionals?Are all non professionals amateurs?
That was not the case in the past, when "Professionals" were limited to the medicine and law (I think - maybe clergy too). The idea of a professional engineer was new in the 19th century[1]. Even now, it implies more than just being paid - but a particular degree of competence and/or membership of a professional body. Like CI5
[1] Reference: A program I saw on telly once. I forget which one.