1
general::
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.
American Heritage Idioms
2
general::
Phrase(s): die for someone or something
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.
McGrawhill's American Idioms And Phrasal Verbs