pendentive(triangular section of vaulting) noun [UK: pendˈentɪv] [US: pendˈentɪv]
plume [plumes](cluster of feathers worn as an ornament) noun [UK: pluːm] [US: ˈpluːm]Mount Etna has erupted, sending lava and ash plumes into the Sicilian sky. = Il Monte Etna ha eruttato, spedendo pennacchi di lava e cenere nel cielo siciliano.