demand vs purchase

demand

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

  • An urgent request. 

  • The desire to purchase goods and services. 

  • An order. 

  • 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. 

verb
  • To require of someone. 

  • To claim a right to something. 

  • To ask forcefully for information. 

  • To request forcefully. 

  • To issue a summons to court. 

purchase

noun
  • That which is obtained for a price in money or its equivalent. 

  • A price paid for a house or estate, etc. equal to the amount of the rent or income during the stated number of years. 

  • The apparatus, tackle or device by which such mechanical advantage is gained and in nautical terminology the ratio of such a device, like a pulley, or block and tackle. 

  • The amount of hold one has from an individual foothold or ledge. 

  • Any mechanical hold or advantage, applied to the raising or removing of heavy bodies, as by a lever, a tackle or capstan. 

  • The acquisition of title to, or property in, anything for a price; buying for money or its equivalent. 

  • That which is obtained, got or acquired, in any manner, honestly or dishonestly; property; possession; acquisition. 

verb
  • To apply to (anything) a device for obtaining a mechanical advantage; to get a purchase upon, or apply a purchase to; to raise or move by mechanical means. 

  • To pursue and obtain; to acquire by seeking; to gain, obtain, or acquire. 

  • To constitute the buying power for a purchase, have a trading value. 

  • To obtain by any outlay, as of labor, danger, or sacrifice, etc. 

  • To buy, obtain by payment of a price in money or its equivalent. 

  • To put forth effort to obtain anything; to strive; to exert oneself. 

  • To expiate by a fine or forfeit. 

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