Purchasing power refers to the amount of goods and services that can be bought with a specific amount of money. It measures how much we can get for our money in terms of what we can afford to purchase. Full definition
You'd be agreeing to a deal that would guarantee you a loss of purchasing power of $ 40 each year. (soundmindinvesting.com)
Inflation is the general increase in prices that happens every year and the decline in purchasing power of your money. (thecollegeinvestor.com)
Inflation seems to be rarely considered when looking at investments, but it should be especially in retirement as the greatest threat at that time is the loss of purchasing power over time. (dividendmonk.com)