I girl from Australia or New Zealand chick that is flat chested slut who you have sex with..
A Flatmate is; A flat chested girl from the the south pacific, generalized towards Kiwis and Aussies chick, whom were not "blessed" with tits!
1. A femail friend with small or non-existant mammaries
2. A person who lives in the same flat as you.
What do you think of Emma?
I'm going for a beer with my flatmates.