The son of Ar-Adûnakhôr and the 21st ruler of Númenor, whose Quenya name was Tar-Hostamir “*Many-jewels” (UT/222). The first element zimra “jewel” of his Adûnaic name seems to have the same meaning as the last element -mir of his Quenya name. The first element ᴹQ. hosta of his Quenya name means a “large number”, and this might be the meaning of the last element -thôn of his Adûnaic name, as suggested by Carl Hostetter and Patrick Wynn (AAD/23).
Andreas Moehn instead suggested (EotAL/ZIM’R) that the final element -ôn may be the same as the final element of Pharazôn and that the entire name is an agental-formation of an unattested verb zimrathâ- “gather jewels”. This makes the literal meaning “Jewel-gatherer”, which fits if you assume (as Mr. Moehn suggested) that the initial element of Quenya name is actually the verb Q. hosta- “to gather” so that Hostamir = “*Gather-jewels”.