praenomen
A first name or given name; particularly the first of the tria nomina (three nouns) borne by free male Roman citizens.
Julius Caesar's praenomen was Gaius.
The throne name of a pharaoh, the fourth of the five names of the royal titulary, traditionally encircled by a cartouche and preceded by the title nswt-bjtj.
historical
Tutankhamun's praenomen or throne name was Nebkheperrure, "Lord of the forms of Ra".
The genus name in a binomial scientific name.
In the name Tyrannosaurus rex, "Tyrannosaurus" is the praenomen.
Where it comes from
From Latin praenōmen, from prae- (“pre-: before”) + nōmen (“name, family name”).
Adapted from the Wiktionary entry praenomen (CC BY-SA 4.0).