sandal

From Middle English sandal (“sandal”), from Old French sandale, from Latin sandalium, from Ancient Greek σανδάλιον (sandálion), diminutive of σάνδαλον (sándalon, “sandal”), of unknown origin. Often mistakenly parsed as related to sand.

From Arabic صَنْدَل (ṣandal), the same word as the shoe sandal, just applied for boats of the shape of this shoe.