What is Millie Millbag, Milliard?
1.
A millie is a Northern Irish FEMALE Chav. The term has been around long before chav existed.
It goes back to the days when the rough and working class fishwives worked in the Linen Mills, hence millie.
The male equivalent is 'spide'. Its roots and origins are unknown, but spides normally hang around corners with massive carryouts and hurl abuse at passersby.
Don't wear that cheap transparent white dress, you look like a millie.