n. The character of being empirical; reliance on direct experience and observation rather than on theory; empirical method; especially, an undue reliance upon mere individual experience.n. In medicine, the practice of empirics; hence, quackery; the pretension of an ignorant person to medical skill.n. The metaphysical theory that all ideas are derived from sensuous experience—that is, that there are no innate or a priori conceptions.