Meaning

• Any activity designed to develop or hone a skill or ability.

  "The teacher told us that the next exercise is to write an essay."

• Activity intended to improve physical, or sometimes mental, strength and fitness.

  "I do crosswords for mental exercise."

• A setting in action or practicing; employment in the proper mode of activity; exertion; application; use.

  "The law guarantees us the free exercise of our rights."

• The performance of an office, ceremony, or duty.

  "I assisted the ailing vicar in the exercise of his parish duties."

• That which gives practice; a trial; a test.

Meaning

• To exert for the sake of training or improvement; to practice in order to develop.

  "to exercise troops or horses;  to exercise one's brain with a puzzle"

• To perform physical activity for health or training.

  "I exercise at the gym every day."

• To use (a right, an option, etc.); to put into practice.

  "She is going to exercise her right to vote."

• (now often in passive) 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.

  "exercised with pain"

• To set in action; to cause to act, move, or make exertion; to give employment to.