What is the definition of CPI

I'm pretty sure you're asking for the definition of 'Consumer Price Index', if not I am incredibly sorry. But, if I am correct ... the consumer price index (CPI) measures changes in consumer prices. The Bureau of Labor Statistics (BLS) calculates and publishes CPI data each month. It is the most recognized and known inflation measure in the US. Basically, CPI measures the change in the retail prices of a huge amount of specific goods and services, which is called the market basket. This falls into eight major categories: food and beverage, housing, apparel, transportation, medical care, recreation, education and communication, and other.

A measure that examines the weighted average pf prices of a basket of consumer goods and services, such as transportation, food, and medical care.