Thank you so much! Works perfectly with wikitaxi.
Note for other people trying to use the dump: because it's gzipped, wikitaxi cannot interpret it (I was surprised that it couldn't... really if you can support one of the archive formats, another one shouldn't be too far away. But whatever, it works). On unix systems you probably know of a compression utility to convert to bz2; on windows you'll need 7zip.
Download the dump and open it in 7zip, then extract the xml file inside. Create a new archive in 7zip and make sure the archive format is bzip2. Add the dump xml to this archive (not the gz file you downloaded, but the xml file itself).
You need wikitaxi
to read the dump. Taxi leaves some things to be desired and it's a bit rudimentary, but it's basically the only program available that's capable of doing this job. Extract wikitaxi into any folder of your choice (it's a self contained prog and needs no installation) then run the wikitaxi importer. Select the bz2 archive you just made with 7zip. Wikitaxi importer will convert the bz2 archive into a .taxi file that wikitaxi uses to interpret the wiki database, so you also need to tell the importer where to output the taxi file. Then run the importer to create the taxi file itself.
Finally, open up wikitaxi and go to options, then select "open .taxi file" and select the taxi file you just created. You will now have access to the DF wiki offline! You can search the wiki using the bar at the top of wikitaxi window. Because the DF wiki is so reliant on redirecting general links to a particular namespace (for example when you go to wiki/noble, it's actually going to redirect you to wiki/DF2012:Noble), those redirects don't seem to play perfectly with wikitaxi, so you'll have to rely on the search bar for most of your reading. For example, if you're looking for the nobles page, your best bet is to search DF2012:noble. Nevertheless, I can confirm that it works!
EDIT: some alternatives to taxi can be found here
but I have yet to try any of them. In general most of these programs listed are server frontends for the mediawiki software, so they're not exactly introductory to install. I have a bit of experience with XAMPP so I could try most of them (I bet I could even load up mediawiki on a local server and just run the dump out of that somehow), but wikitaxi is still prob the easiest solution since it wraps the code in a pretty little reader interface.