A girl between the ages of 13 and 19 who only likes something because it's cute or 'hawt'. They are usually stupid too, and most likely vain.
Air headed teenage girl - OMG! I totally love this band!
Non air-headed girl - Oh, what do they sing?
Air headed teenage girl - I dunno, but the singer's HAWT!!!!
Non air-headed girl - You're such an air-head...
Air-head - What's an air-head?