You have no socially named relationship to your step-great-grandson-in-law's father. If you like, you might call him "son" or "Mr. ...." or simply call him by his first name.
What does a tuba call its father? ooompapa
Your father's father is your grandfather.
In Bicolano, you would call father "amá" or "ama".
you call a father whale in dad blue whale
You can call father “ପିତା” (pita) in Oriya.
a step father.
your father in law
Yes, it is justified to call him the father of modern embryology.
"Uncle" is your father's brother.
He called his father "chichi-we".
Your father's brother is your uncle.
He is your Father in law.