My favorite words to say in various languages:  Esperanto:  insekoj, Portuguese:  liquidificador, German:  Flammenwerfer.  I'm not sure I have a favorite Spanish or English word.  Maybe the longest one for English:  antidisestablishmentarianism.  I'll have to think about Spanish.
@hobbsc  my favourite Portuguese word could be #metralhadora. The word looks nice to me. Too bad it translates as machine gun, so it just cannot be a favourite word.
@mcscx2 well, flamethrower is a violent word. Those are all just fun to say.