Correspondence Principle

The principle that when a new, more general theory is put forth, it must reduce to the more specialized (and usually simpler) theory under normal circumstances. There are correspondence principles for general relativity to special relativity and special relativity to Newtonian mechanics, but the most widely known correspondence principle (and generally what is meant when one says "correspondence principle") is that of quantum mechanics to classical mechanics.

N. Bohr

Correspondence Limit The limit at which a more general theory reduces to a more specialized theory when the conditions that the specialized theory requires are taken away.

N. Bohr