Slapper

n.

Heard in Dublin, Galway, Longford and Waterford

A promiscuous young woman; a slut.

In use

She's only a slapper" "Hey would you look at that one shes a right slapper

Posh English

She is nothing but a lady of easy virtue. Good heavens, would you look at that one. She is a thoroughly promiscuous young woman.

Same phrase, other counties