practice (v.)

c. 1400, "to do, act;" early 15c., "to follow or employ; to carry on a profession," especially medicine, 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 perform repeatedly to acquire skill, to learn by repeated performance;" mid-15c. as "to perform, to work at, exercise." Related: Practiced; practicing.

practice (n.)

early 15c., practise, "practical application," originally especially of medicine but also alchemy, education, etc.; from Old French pratiser, from Medieval Latin practicare (see practice (v.)). From early 15c. often assimilated in spelling to nouns in -ice. Also as practic, which survived in parallel into 19c.

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Definitions of practice from WordNet
practice (v.)
carry out or practice; as of jobs and professions;
practice law
Synonyms: practise / exercise / do
practice (v.)
learn by repetition;
Pianists practice scales
Synonyms: drill / exercise / practise
practice (v.)
engage in a rehearsal (of);
Synonyms: rehearse / practise
practice (v.)
avail oneself to;
practice a religion
practice non-violent resistance
Synonyms: apply / use
practice (v.)
engage in or perform;
practice safe sex
Synonyms: commit
practice (n.)
a customary way of operation or behavior;
it is their practice to give annual raises
Synonyms: pattern
practice (n.)
systematic training by multiple repetitions;
practice makes perfect
Synonyms: exercise / drill / practice session / recitation
practice (n.)
translating an idea into action;
a hard theory to put into practice
Synonyms: praxis
practice (n.)
the exercise of a profession;
I took over his practice when he retired
the practice of the law
practice (n.)
knowledge of how something is usually done;
it is not the local practice to wear shorts to dinner