Why do you call Mexicans hispanic when Hispanic comes from Spain not Mexico?

I am a caucasian HISPANIC. I am not an anglo. Mexicans are not Hispanic. Their origins are not fully Spain. Hispanic means like Ururguay and the Spaniards of Argentina and Spain. Mexico Peru and Guatemala? Not Hispanic unless you are a criollo. Why do you want to take our identity away? You apply OUR WORD to a bunch of indians.