Yep, that is what I meant. Create new page is less exposed now we've moved the Arbital math home. It's accessible via the hamburger menu in the top right still, and you can link to it like this, but that's not particularly easy to find. I'm pretty sure we'll want to improve that, and generally make it easier to navigate between the wiki and discussion areas of Arbital.
Yep, I think when we've got good support for browsing by tag we'll be able to tag things with #term or #definition, and it'll work?
By splits I just meant if people disagree they could make alternate terms, maybe crosslinking with "maybe you want this term"? No special features.