The definition of a rip off is a product that is not worth the cost or a scam that you fall victim to that causes you to pay more than something is worth.(noun)
To rip off is to cheat or steal from someone.(verb)
An example of rip off is when you ask someone for money for a product that you will buy them, take the money and never deliver.
See rip-off in Webster's New World College Dictionary
See rip-off in American Heritage Dictionary 4
Learn more about rip-off