Ar-Belzagar
From Tolkien Gateway
Tar-Calmacil was a great warrior who succeeded his father Tar-Alcarin to become the eighteenth King of Númenor. In his time, the falling away of the Númenóreans that had begun centuries earlier in the reign of Tar-Atanamir became stronger, and he was the first King whose name was translated into the native Adûnaic speech of Númenor: Ar-Belzagar. Both names apparently mean 'King Light-sword', a reference to his warlike youth.