Pastel
Cheap-looking
Fur
Cap sleeves
A fitted woven top with no bust darts (it will gape even if it's roomy enough, I've learned)
High heels (over 3 or so inches, though I'll go a bit higher if there's a platform)
Skinny heels
Shoes that are narrow through the toe box
Fussy details
Ruffles, usually
Novelty buttons
Cut for a pear-shape, if it's a dress or coat (small on top, roomy on the bottom)
3/4 sleeved tops with gathered, banded sleeves
Tops with lots of embellishments, e.g., plastic stones, chains, etc.
ETA after reading everyone's posts: strapless, bling, asymmetrical shoulders/sleeves, velour, shiny poly satin, logos (hate!), empire waist, low-rises