thunder   
ampy
the thunder which comes near [Richardson 1885]
kotroka
thunder; the sound of falling water [Hallanger 1973]
mikotroka
to thunder; to roar, as a cascade, etc [Hallanger 1973]
rohona
rohondrohona
a sound like thunder [Hallanger 1973]
varatra
thunder; a thunderbolt [Hallanger 1973]