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1. Derived from experiment and observation rather than theory
   "empirical laws"; "an empirical treatment of a disease about which little is known";
   - empiric
    
2. [archaic] Relying on medical quackery
   "empirical treatment";
   - empiric [archaic]

See also: a posteriori, confirmable, data-based, existential, experiential, experimental, falsifiable, observational, semiempirical, trial-and-error, verifiable

Antonym: theoretic

Encyclopedia: Empirical