demand vs ply

demand

verb
  • To request forcefully. 

  • To require of someone. 

  • To claim a right to something. 

  • To ask forcefully for information. 

  • To issue a summons to court. 

noun
  • An urgent request. 

  • The desire to purchase goods and services. 

  • An order. 

  • The amount of a good or service that consumers are willing to buy at a particular price. 

  • A forceful claim for something. 

  • A requirement. 

  • More precisely peak demand or peak load, a measure of the maximum power load of a utility's customer over a short period of time; the power load integrated over a specified time interval. 

ply

verb
  • To press upon; to urge persistently. 

  • To work at (something) diligently. 

  • To persist in offering something to, especially for the purpose of inducement or persuasion. 

  • To travel over (a route) regularly. 

  • To bend, to flex; to be bent by something, to give way or yield (to a force, etc.). 

  • To wield or use (a tool, a weapon, etc.) steadily or vigorously. 

noun
  • In two-player sequential games, a "half-turn" or a move made by one of the players. 

  • A layer of material. 

  • A bent; a direction. 

  • A strand that, twisted together with other strands, makes up rope or yarn. 

  • A condition, a state. 

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