What does Leōnidās mean in Latin?

Leōnidās, a proper noun, means “A king of Sparta, who fell at Thermopylae.”.

What is the genitive of Leōnidās?

The genitive singular is Leōnidae. Leōnidās is masculine, first declension.

In classical Latin, [ɫeˈoː.nɪ.daːs]; in ecclesiastical (church) Latin, [leˈɔː.ni.das].

proper noun · masculinefirst declension

Leōnidās m sg (genitive Leōnidae)

Classical[ɫeˈoː.nɪ.daːs]Ecclesiastical[leˈɔː.ni.das]

Lĕōnĭdas (nom. Lĕōnĭda, Just. 2, 11, 2), ae, m., = Λεωνίδας.

I. A king of Sparta, who fell at Thermopylæ, Cic. Fin. 2, 30, 97; 2, 19, 62; id. Tusc. 1, 42, 101; 1, 49, 116; Nep. Them. 3.—

II. The name of a slave, Plaut. As. 1, 1, 43 al.; v. also Leonides.

Borrowed from Ancient Greek Λεωνίδᾱς (Leōnídās, “son of Leon / a lion”).