Best friend thinks she's so smart? ?

She thinks she's so smart. She uses big words when she speaks to me (okay, this doesn't bother me that much, but I know she does it to make me feel inferior... especially since she thinks I'm ditzy) and is constantly calling other people stupid. She also thinks that she's too smart to wear makeup or dress nice. I don't want to be shallow, but it just annoys me. Would it be rude if I tell her about this? I don't want to be rude, that's so not me, but I'm getting sick of it.