An argument in which one member gets completely out witted by the other, over and over again.
Laura: Are your parents siblings?
kate: no. your face is so obsure your parents obviously aren't.
Laura: that makes no sence mayte.
Kate: Yes it does. it means their genes must be very different to create that mug.
Laura: bad comeback then dear.
kate: no, you're just too stupid to get it.
there you have it, the original slayathon.