Idea: Combine smart and snide and make snart. Sounds kind of rude: He thinks he’s so snart.
1. Sounds too much like smart.
2. Snarky already does the trick.
3. Snart already exists, apparently, with a different meaning: “when one farts and sneezes at the same time, regardless of which causes which,” as so eloquently defined by the Urban Dictionary.
Solution: Instead, how about snartsy? Sounds like snart, snarky and artsy-fartsy all rolled up into one. For example, Mr. Snartsy Pants sounds even more insulting than Mr. Smarty Pants.