|Origin:||Probably from guaranty|
guarantee2 S2 [countable]
a formal written promise to repair or replace a product if it breaks within a specific period of time [= warranty]:
They offer a two-year guarantee on all their electrical goods.
come with/carry a guarantee
Our computers come with a one year guarantee.
Is your TV under guarantee (=protected by a guarantee)?
a formal promise that something will be done
I'm afraid there's no guarantee of success.
a promise that you will pay back money that someone else has used or borrowed, if they do not pay it themselves
something valuable that you give to someone to keep until you have done something you promised to do:
The bank is holding the airline's assets as guarantees.