Cascarrabias and gruñón mean the same thing and they are the best translation for "grumpy". Ese hombre cascarrabias/gruñón nunca saluda a nadie. That grumpy man never says hi to anybody. Enfadado means angry. Ella está enfadada conmigo porque no quiero ir a la fiesta. She is mad at me because I do not want to go to the party. De mal humor and malhumorado also mean the same thing and can be translated as "to be in a bad mood". Estoy de mal humor porque todo me ha salido mal hoy. I am in a bad mood because everything went wrong today. I hope this helps you.

Ninguna palabra es mejor. Todos significan lo mismo y son usadas en la misma proporción.

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