Definition of "ditzy"

The guy tossed some cash on the counter, then left with the ditzy girl and Abigail's fan.

2011, Ellen Block, The Definition of Wind: A Novel, Bantam, page 31

[…] —and she'd smile like a primly mischievous Japanese girl, or like some slyly ditzy ingenue on a talk show, all the while watching her interrogator try to fathom (though sometimes they were pretty dim and just said, “Oh”) the surprising cleverness of her answer.

2013, Francisco Goldman, The Long Night of White Chickens, Grove Press , Seven

After hiring a crew of young guys and gals including loyal Jo, unlucky-in-love Frankie, strapping Bob, wisecracking Dee Dee, ditzy blonde Jonesy and titian-haired Penny, the gang drives up to the lodge.

2015, Thomas Lisanti, Hollywood Surf and Beach Movies: The First Wave, 1959–1969, McFarland, page 262