In this post's comment section alone many use the term "open source" but really mean to say "public-source", others use the two terms interchangeably even when they seem to be aware of the distinction, and then there are people who seem to think that by making your GitHub repo public it becomes OSD-spec "open source" and with that free to use.

It's just so confusing and easy to misinterpret each-others' true meaning.

Thanks for making me aware of the existence of that OSD OSS spec btw! Came across the (recovered) blog post where the term was first announced http://www.catb.org/~esr/open-source.html.