exercise vs fee

exercise

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

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

  • To perform physical activity for health or training. 

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

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

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

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

fee

verb
  • To reward for services performed, or to be performed; to recompense; to hire or keep in hire; hence, to bribe. 

noun
  • A right to the use of a superior's land as a stipend for certain services to be performed, typically military service. 

  • An additional monetary payment charged for a service or good that is minor compared to the underlying cost. 

  • Synonym of fief: the land so held. 

  • An inheritable estate in land, whether absolute and without limitation to potential heirs (fee simple) or with limitations to particular kinds of heirs (fee tail). 

  • An inheritable estate in land held of a feudal lord on condition of performance of certain services, typically military service. 

How often have the words exercise and fee occurred in a corpus of books? (source: Google Ngram Viewer )