Vag clap competition
Originated in Brisbane, Australia.

When two or more women have to one up each other. This is usually done through verbal combat, where the second woman will try to discredit the first with an equal or better story. The first woman will generally retaliate, with a further ‘one-up’ and so it continues.

This is called a ‘vag clap competetion’ because the one-upwomanship is like watching two women clap their vagina’s at each other - completely useless and no way to win an argument.
Susan: I got this dress for a bargain! It was on sale.

Claire: Well I got a new dress, and the sales assistant through in a pair of shoes for free.

Susan: well I saved so much from the dress being on sale I could also get this handbag and a scarf.

Claire: well the sales assistant also gave me a $50 voucher.

Brian: for goodness sake, stop having a vag clap competition!