when a woman has a baby with her brother

Kid and Mother's Brother = Uncle
Kid and Mother's Baby Daddy + Daddy
-------
Uncle Daddy
Timmy's mom is so ugly no man ever loved her except for her brother, literally.

Mom+Brother=Nephew Son or "Timmy"

It also can be the otha side around, Auntie Mama. Pretty much the same concept as Uncle Daddy.
by MayaEA December 18, 2006
Get the uncle daddy mug.
When you have sex with your sister and get her pregnant, and she keeps the baby, that makes you UNCLE DADDY
Me and my sister , I mean your mom wondered if you were gonna take me, your UNCLE DADDY or her, your AUNT MA to the parent teacher conferences? Being that your almost old enough to vote and still in the first grade.
by Katelynne's dad March 23, 2013
Get the UNCLE DADDY mug.
1. N. Originally, a man who adopts a dog from the pound/humane society. 2. Now also refers to a boss, a playa, a pimp.
The vet asked if I was Mabel's uncle daddy and if I would authorize an anal exam.

The uncle daddy sez so, that's why.
by The uncle daddy February 1, 2005
Get the uncle daddy mug.
When suck so bad at being a dad, you're demoted to Uncle.
He is so pathetic, that fool couldnt even get to the bus stop on time, i'm demoting him to uncle-daddy.
by DaddyLexx May 28, 2019
Get the Uncle-Daddy mug.
An uncle that plays daddy to a kid that is not his and not telling the child that the uncle is really the daddy.
Uncle-daddy no, one or the other...
by Jack breeazy December 28, 2016
Get the Uncle-daddy mug.