Manic Pixie Dream Girl
She's stunningly attractive, high on life, full of wacky quirks and idiosyncrasies (generally including childlike playfulness and a tendency towards petty crime), often with a touch of wild hair dye. She's inexplicably obsessed with our stuffed-shirt hero, on whom she will focus her kuh-razy antics until he learns to live freely and love madly.
Kirsten Dunst in Elizabethtown is a MPGD
Natalie Portman's in Garden State is a MPDG
Zooey Deschanel's in (500) Days of Summer, other films, and especially in the TV show New Girl is a MPDG