1.Lit. to perish for the benefit or glory of someone or something. He said he was willing to die for his country.She would die for her child if necessary.
2.Fig. to experience great physical or emotional desire for someone or something. He was just dying for Jane, but she would have nothing to do with him.Freddie was dying for a glass of water—he was so thirsty.
Also, be dying for. Long for, desire excessively, as in I'm dying for some ice cream. This hyperbolic usage dates from the late 1500s. Also see die to.