I'm wondering if anybody knows if the term Sacred Cow refers to the Indian (as in person from india) belief in cows being reincarnated people or the part in Homer's Oddessy where the crew eats the sacred kine of helios and they get killed because of it?
According to your friend and mine, Merriam Webster, it's from "the veneration of the cow by Hindus". The definition notes that sacred cows are often "unreasonably" immune from criticism as well, heh.