1) n. custom or habit as shown by repeated action, as in "it is the practice in the industry to confirm orders before shipping." 2) n. the legal business, as in "law practice," or "the practice of the law." 3) v. to repeat an activity in order to maintain or improve skills, as "he practices the violin every evening." 4) v. to conduct a law business, as "she practices law in St. Louis."