Term given to a girl or group of girls who are under the age of consent, and socialise with older guys. A group of 13-15 year old girls who hang around with a group of 16-18 lads would be perfectly described as illegalites.
"Man, Smithy drank 3 litres of cider on Friday night then poked that illegialite around the back of the shops, what a legend!"
or
"Thoose illegalites are a bunch of sluts Mikey, but i love it!"
the state of everything being illegal, but that means everything being illegal, is illegal, which makes a paradox, but that also means a paradox is illegal.