Usually a young woman of wealthy / extremely comfortable origin who is also very attractive and knows it. She can be seen either at the gym trying not to look repulsed by the smell of sweat; 'modelling' Abercrombie & Fitch clothes; thinks herself above WAGs, but secretly reads celebrity magazines for fashion tips. Attends university (of course) though is not very bright, & can sometimes be seen in the student union 'slumming it' - looking down on anyone with left wing opinions.
Also can be seen walking down the high street thinking she's a catwalk model.
Man 1: 'By jove that's a prime piece of yuppie
Man 2: 'Oh Gideon you're SOOOO 1980s; that's a snotty totty'.