look up any word, like sapiosexual:
 
1.
When everyone in your group of friends sleeps with each other.
"OH MY, SO SHAYNA IS GOING OUT WITH MY EX?"
"Yeah man, she's going out with Jordan.. remember him and I went out back in grade 9"
"Woah dude, talk about interbreeding."
by Roeanna December 17, 2007
3 1
 
2.
When you go around fecking your frikin sister, mother, aunt, grandma, ect.

A redneck
Johnny realized he was lonely. He found his sister and practiced interbreeding.
by tabbhighschoolhornyguys March 22, 2005
5 3
 
3.
If you live in the Anglia region, you will know...
"who's that looker over there?"
"thats your sister"
"oh shit, i've got to marry her next week, she's got child bearing hips"
by Square Bob Sponge Pants June 11, 2003
4 5