somebody who has adopted you, somebody your mom had you with, someone you love, etc. sometimesthey are someone your mom doesn't love. they are called baby daddies.
In male prisons, a prisoner who is always the pitcher, man or top, i.e. the penetrator or recipient of fellatio, in same-sex relations with a prisoner who is the catcher, girl or boy, i.e. the penetrated or fellator.