rōþor n (nominative plural rōþor)
From Proto-Germanic *rōþrą (“rudder", literally "paddle, instrument for rowing”) (compare Old Frisian rōther, Old High German ruodar), from Proto-Germanic *rōaną (“to row”), from Proto-Indo-European *h₁reh₁- (“to row”) + Proto-Germanic *-þrą, *-þraz, instrumental suffix; equivalent to Old English rōwan (“to row”) + -þor. More at row.