1. [n]  the activity of exerting your muscles in various ways to keep fit; "the doctor recommended regular exercise"; "he did some exercising"; "the physical exertion required by his work kept him fit"
2. [n]  a task performed or problem solved in order to develop skill or understanding; "you must work the examples at the end of each chapter in the textbook"
3. [n]  systematic training by multiple repetitions; "practice makes perfect"
4. [n]  the act of using; "he warned against the use of narcotic drugs"; "skilled in the utilization of computers"
5. [n]  (usually plural) a ceremony that involves processions and speeches; "academic exercises"
6. [v]  do physical exercise; "She works out in the gym every day"
7. [v]  give a work-out to; "Some parents exercise their infants"; "My personal trainer works me hard"; "work one's muscles"
8. [v]  learn by repetition
9. [v]  put to use; "exert one's power or influence"
10. [v]  carry out or practice; as of jobs and professions; "practice law"

Exercise
Exercise

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1. \Ex"er*cise\, n. [F. exercice, L. exercitium, from
   exercere, exercitum, to drive on, keep, busy, prob. orig., to
   thrust or drive out of the inclosure; ex out + arcere to shut
   up, inclose. See {Ark}.]
   1. The act of exercising; a setting in action or practicing;
      employment in the proper mode of activity; exertion;
      application; use; habitual activity; occupation, in
      general; practice.
            exercise of the important function confided by the
            constitution to the legislature.      --Jefferson.
            O we will walk this world, Yoked in all exercise of
            noble end.                            --Tennyson.
   2. Exertion for the sake of training or improvement whether
      physical, intellectual, or moral; practice to acquire
      skill, knowledge, virtue, perfectness, grace, etc.
      ``Desire of knightly exercise.'' --Spenser.
            An exercise of the eyes and memory.   --Locke.
   3. Bodily exertion for the sake of keeping the organs and
      functions in a healthy state; hygienic activity; as, to
      take exercise on horseback.
            The wise for cure on exercise depend. --Dryden.
   4. The performance of an office, a ceremony, or a religious
      duty.
            Lewis refused even those of the church of England .
            . . the public exercise of their religion.
                                                  --Addison.
            To draw him from his holy exercise.   --Shak.
   5. That which is done for the sake of exercising, practicing,
      training, or promoting skill, health, mental, improvement,
      moral discipline, etc.; that which is assigned or
      prescribed for such ends; hence, a disquisition; a lesson;
      a task; as, military or naval exercises; musical
      exercises; an exercise in composition.
            The clumsy exercises of the European tourney.
                                                  --Prescott.
            He seems to have taken a degree, and performed
            public exercises in Cambridge, in 1565. --Brydges.
   6. That which gives practice; a trial; a test.
            Patience is more oft the exercise Of saints, the
            trial of their fortitude.             --Milton.
   {Exercise bone} (Med.), a deposit of bony matter in the soft
      tissues, produced by pressure or exertion.
   

2. \Ex"er*cise\, v. t. [imp. & p. p. {Exercised}; p. pr. &
   vb. n. {Exercising}.]
   1. To set in action; to cause to act, move, or make exertion;
      to give employment to; to put in action habitually or
      constantly; to school or train; to exert repeatedly; to
      busy.
            Herein do I Exercise myself, to have always a
            conscience void of offence.           --Acts xxiv.
                                                  16.
   2. To exert for the sake of training or improvement; to
      practice in order to develop; hence, also, to improve by
      practice; to discipline, and to use or to for the purpose
      of training; as, to exercise arms; to exercise one's self
      in music; to exercise troops.
            About him exercised heroic games The unarmed youth.
                                                  --Milton.
   3. To occupy the attention and effort of; to task; to tax,
      especially in a painful or vexatious manner; harass; to
      vex; to worry or make anxious; to affect; to discipline;
      as, exercised with pain.
            Where pain of unextinguishable fire Must exercise us
            without hope of end.                  --Milton.
   4. To put in practice; to carry out in action; to perform the
      duties of; to use; to employ; to practice; as, to exercise
      authority; to exercise an office.
            I am the Lord which exercise loving-kindness,
            judgment, and righteousness in the earth. --Jer. ix.
                                                  24.
            The people of the land have used oppression and
            exercised robbery.                    --Ezek. xxii.
                                                  29.
   

3. \Ex"er*cise\, v. i.
   To exercise one's self, as under military training; to drill;
   to take exercise; to use action or exertion; to practice
   gymnastics; as, to exercise for health or amusement.
         I wear my trusty sword, When I do exercise. --Cowper.