Tar-Hostamir
From Tolkien Gateway
From the time of the first Kings of Númenor, it had been tradition for the ruler to take a royal name in the Quenya tongue. This tradition stood until the latter half of Númenor's third millennium, when King Ar-Adûnakhôr defied it. He was the first King to take a name in the native Adûnaic language of the Númenóreans, though a Quenya translation of the name was also recorded.
Ar-Adûnakhôr was succeeded by his son, who inherited the Sceptre in the name of Ar-Zimrathôn. Like his father, a Quenya version of his name was also recorded: Tar-Hostamir, where hostamir appears to mean 'collector of jewels'.