1. to regard or treat as of little value or account.
2. to vilify; depreciate.
My big, but admittedly not exhaustive, Oxford Canadian Dictionary (Thumb Index Edition) doesn't have this word. That shocked me because this dictionary has a whole lot of words and I trust it, but I'll take a chance with dictionary.com this week.
I think I'll use vilipend in my normal life. After all, I have a tendency to vilipend things especially if Canadian politics are involved. Or any politics, really, but now that I'm working for the government... In reality, I wish I could simply vilipend them (as in definition 1), but I often find it difficult to be truly dismissive.