Your mother's brother is your uncle.
Your uncle's son, or daughter, is your first cousin.
Your mother's sister's son is your first cousin.
Your mother's brother (or your father's) is your uncle.
You can consider her a great aunt, but only by marriage, not blood
you call him your uncle
Great uncle.
"Uncle -insert his name-"
Aunt
Our cousins are our mothers sisters son :)
cousin
First cousin, once removed.
Your mums brothers sisters roommate flatmates sisters brothers mothers son.
nephew
Your cousin.
nephew!
We would infact, cll our sisters son your nephew and they would call you either auntie or uncle depending on your sex.
your great aunt.
My sister's son is my nephew.
My sister's son is my nephew.
If your sister had a son, then he is your nephew.