empirical

adj

1. Pertaining to or based on experience, as opposed to theory.

   “The lengths were calculated according to the empirical rules of the trade.”

   “For some presumptive diagnoses, empirical antibiotic therapy begins immediately, whereas specific antibiotic therapy must await the results of the culture and sensitivity test.”

   “The village carpenter […] lays out his work by empirical rules learnt in his apprenticeship.”

2. Pertaining to, derived from, or testable by observations made using the physical senses or using instruments which extend the senses.
3. Verifiable by means of scientific experimentation.

   “demonstrable with empirical evidence”

noun

1. A measurement or result achieved by empirical means.