noun, masculine/ˈtɾweno/plural: truenos
a clap of thunder; thunder
Inherited from Latin tonus (“thunderclap; sound, tone”), possibly through a Late Latin or Vulgar Latin *tronus, incremented with an -r- due to influence from *tronitus < tonitrus. Alternatively a derivative of tronar. Compare Galician trono, Portuguese trom, Occitan tron, old Italian trono, Sicilian tronu.