Zettinamus

Zettinamus is equal to \(f_{\psi(\upsilon[10^{21}])}(10)\). The term was coined by Denis Maksudov

Etymology
The 3 parts of the name, "zetto", "in" and "amus", mean \(10^{21}\), the "in-" operation. So the full name indicates the ordinal index of the number.