Your children and your niece are first cousins to each other.
There is none. "This is George, my niece's husband." In most families he would referred to as a nephew.
Your mother's uncle, whether maternal or paternal, is your great uncle. You are his great nephew if you are male, and his great niece if you are female.
She is your niece, you are her aunt or uncle.
Yes, Ragini Khanna is Govinda's niece; Govinda is her maternal uncle.
Your daughter and your aunt's children are first cousins to each other. Your daughter and your aunt's grandson are first cousins, once removed, to each other.
You are your uncle's niece. You and your uncle's children are first cousins to each other.
You are Great Aunt to your niece's child. The child is your great niece or great nephew.
Either they are second cousins or technically not related at all. Your cousin's niece would be one of her siblings' children, in which case it would one of your cousin's daughters, or her spouses' niece, in which case there is no blood relationship, but most families would refer to them as a cousin.
You are great great aunt to your niece's grandchild. Your children and your niece's grandchild are first cousins, twice removed.
They are first cousins once removed. Your niece's children and your grandchildren will then be 2nd cousins.
(1) Your niece is the daughter of your sibling (2) Your niece and your children are 1st cousins (3) Your grandchildren and your niece's children are 2nd cousins (4) Your g'children and your niece's g'children are 2nd cousins once removed
Your daughter and your niece are first cousins to each other.
Uncle and niece.
Your brother's daughter is your niece and his granddaughter is your great niece.
They're related to you
they would be cousins.
Your wife's niece is also your niece, and her daughter is your great niece. It is to be hoped that you do not have a relationship WITH her, merely TO her.