Goths) Etymology Latin vallus derives from Proto-Indo-European *walso-, " a post". Vallus is the source of English wall. The word vallus is sometimes used as equivalent to vallum (Caesar, Bell. Civ. iii.63). References "A Dictionary of Greek and Roman Antiquities". William Smith, LLD. William Wayte. G. E. Marindin. Albemarle Street, London: John Murray, 1890. Roman vallum