Alcarondas

Alcarondas a.k.a. Castle of the Sea was Ar-Pharazôn's ship at the head of a great armada of the Great Armament.

The ship was as lavish as it was martial with many Golden masts and specially made throne for the king. Like most of the ships in the fleet, it was staffed with many strong slaves to man the oars when the wind wasn’t in their favor.

Etymology
The name maybe Adûnaic but seems more Quenya in form and pronunciation.