adj. Not sure how half-wombats are doing on standardized tests these days, but this is likely not a compliment.
Real citation: "I'll tell ya what the real bloomin' deal is! The real bloomin' deal is that some half wombat brained twit isn't out there burgling them turds! :P x"
(Dec. 16, 2008, MySpace, http://comment.myspace.com/index.cfm?fuseaction=user.viewComments&friendID=300775193)
Made-up citation: "I'd rather be a half-wombat-brained buttmunch than a quarter-chicken-feathered assmunch. But that's just me..."