Enough that when someone says die its not one and 99 percent of the time means you want to kill them.
Mihawk says to Zoro "DIE!" and proceeds to slash him.
Then turns around and tells Luffy "Don't worry, he's not dead."
Mihawk had no intention of killing Zoro. So when he told him "Die" it was not meant to be taken in a literal sense, hence it was a figure of speech for dramatic effect.