The software comes with a 'money-back guarantee'. [=a promise that the money you spend on a product will be returned if the product is not good enough]
We used our house as a 'guarantee' for the loan. [=we said that the bank could take our house if we did not pay back the loan]
There is no 'guarantee' that they will approve the contract. [=there is no way to be sure that they will approve it]
(..) How many counts in that movement you just eXecuted?. -Sir, four counts, sir. -What's the idea of looking in the chamber?. Sir, to guarantee the private is not giving the inspecting officer a loaded weapon, sir. What's your fifth general order?. Sir, the fifth general order is to quit my post (..)1987 Full Metal Jacket