lava: "molten rock issuing from a volcano," 1750, from Italian (Neapolitan or Calabrian dialect) lava "torrent, stream," traditionally said to be from Latin lavare "to wash" (from PIE root *leue- "to wash").
oratory: "small chapel for prayer or worship," early 14c., oratorie, from Old French oratorieand directly from Late Latin oratorium "place of prayer".
"formal public speaking; the art of eloquence," 1580s, from Latin (ars) oratoria"oratorical (art).