Risa

Serious Answer:

It doesn't "stand for" anything in that it's not an acronym or acrostic.

It's the name of Star Trek's "work prison." People can't exactly be fired or ejected from starfleet; it's kind of like a PIP, but instead making it mildly unpleasant until you get bored and leave of your own accord.

On one notable occasion, Captain Janeway was sent there.

Before she left, Commander Chakotay asked her to check in on a friend of his who had been there for years.

You see the wooden statue in the sidebar over there? --->

That thing. It has a name. I don't remember what it's called.

What Chakotay didn't tell her is that his friend was literally a block of wood. In fact, that's why he was at Risa. So Janeway was just like "yeah, I really don't understand what's happening but after asking for an introduction to this dude I have been sent to this little statue like 6 times. I guess there's something to it." So she just kinda carried it around with her for the day, had it hanging out on the table next to her while she was reading and eating and, well, changing clothes. With predictably awkward/hilarious results.

So yeah. This community is named after Star Trek's hilarious take on how to deal with subpar job performance. In the end, Risa was actually a pretty chill place. The perfect place for low effort Star Trek related memes and shitposts.