Kentucky Uncle
A man who has a child with his sister, which makes him both the uncle and the father.
Oh man, I bet Sam has a Kentucky Uncle because of how stupid he is.
Kentucky Uncle
When a man is brushing his teeth while taking a shower and the paste drops down and lands on ones meatus causing a stinging sensation.
I was trying to get a head start to my day by brushing my teeth in the shower and accidentally gave myself a Kentucky Uncle.