Wow, I found the first few pretty darned interesting!

agelast (AY-jel-ast) n. someone who never laughs.
Oh, how awful this would be! I can't imagine never laughing.

dystopia (dis-TOE-pee-ah) n. 1. an imaginary place or state in which the condition of life is extremely bad, as from deprivation, oppression, or terror. 2. a work describing such a place or state.
The opposite of utopia, then? Do the the dys- and u- prefixes signify opposites in other words?

suist (SOO-ist) n. one who follows his own inclinations; a self-pleaser.
Yikes--not what you'd think!

vinculum (VING-kyoo-lum) n. 1. a bond of union; a tie. 2. a straight line drawn over two or more mathematical terms denoting these are subject to the same operations by another term.
This HAS to be of Latin origin, surely?