A point I made myself, and I didn't say otherwise. I also clearly mentioned that was the formal definition, not a working definition.

In mathematics and computer science that is indeed the proper definition.

And HackerNews is definitely a mathsy/computersciencey sort of a place, so it might be nice to use the word correctly here.

Out of interest (or is it flippancy?), where do you use the word algorithm, when not talking about mathematics or computing?

Do you consider a discussion about heuristics vs algorithms (which is what this thread is above), on a site like Hacker News, to be 'general language'...? Or would you consider that this might indeed be a suitable context to comment on their proper formal definitions?