your great uncle
Your mother's son is your brother or your half brother.
He is your god brother.
Your half-brother...
A cousin brother means , the son of the father or mothers , brother or sister.
papu
That would be an uncle.
The son of either your sister or your brother is your nephew. The English language does not make a distinction in that.
The word for uncle in Hindi is "चाचा" (chacha) for father's brother and "मामा" (mama) for mother's brother.
cousin
Your mother's brother is your uncle. Your uncle is your son's great uncle. You are the nephew of your mother's brother. Your son is his great nephew.
Your mom's uncle's daughter is your mothers first cousin. Their son would be your second cousin.
nephew