Ibis is a federated encyclopedia which uses the ActivityPub protocol, just like Mastodon or Lemmy. Users can create, browse, edit articles and use many other features. If you want to start a wiki for a TV series, a video game, or an open source project, then Ibis is for you!
Zim wiki maybe, if you want local only (or vimwiki or EMACS org mode, or even raw markdown, if you’re a shell goblin like myself).