I did in fact search for "RSS memory" and found what I was looking for, but I personally thought it was unclear from context what it was as RSS itself has a very strong association with another acronym (full disclosure: at the beginning of the article I though "consuming 128 MB of RSS" meant that this was an RSS parser that leaked memory) and I was more familiar with the term as a process's "working set size" rather than "resident set size".

Well unless you are not working on a kernel / libc / compiler component, I'm sure that the closest thing to encountering 'RSS Memory' (meaning Residential Set Size which is the memory of a processes that resides in physical RAM but not in swap memory), would be to open up 'top' or 'htop' in the terminal to see that figure.

But no, this isn't an everyday term by average users, but I would expect at least software engineers to be familiar with the term.