late 14c., practisen, "to follow or employ" a course of action; c. 1400, "to do, put into action or practice;" from Old French pratiser, practiser "to practice," alteration of practiquer, from Medieval Latin practicare "to do, perform, practice," from Late Latin practicus "practical," from Greek praktikos "practical" (see practical).
From early 15c. as "to carry on a profession," especially medicine; also "to do or perform repeatedly or habitually with the object of acquiring skill, to learn by repeated performance;" from mid-15c. as "to perform, work at, exercise." Intransitive sense of "perform certain acts repeatedly, train one's self" is by 1590s. Sense of "to cause to practice, teach by exercise, train, drill" is from 1590s. Related: Practiced; practicing.
early 15c., practise, "practical aspect or application," originally especially of medicine but also alchemy, education, etc.; from Old French pratiser, from Medieval Latin practicare (see practice (v.)). It largely displaced the older word, practic, which survived in parallel into 19c. From early 15c. it began to be assimilated in spelling to nouns in -ice.
Sense of "habit, frequent or customary performance" is from c. 1500. Meaning "exercise for instruction or discipline" is from 1520s. Sense of "action, the process of accomplishing or carrying out" (opposed to speculation or theory) is from 1530s. The meaning "regular pursuit of some employment or business" is from 1570s. In 16c.-17c. it also was used in an evil sense, "conspiracy, a scheme."
Practice is sometimes erroneously used for experience, which is a much broader word. Practice is the repetition of an act : as, to become a skilled marksman by practice. Experience is, by derivation, a going clear through, and may mean action, but much oftener views the person as acted upon, taught, disciplined, by what befalls him. [Century Dictionary]