guarantee
n. countablen. a formal promise that something will be done or that a product will work well. If the product breaks, this promise often means you can get your money back or a free repair.
n. a formal assurance, typically in writing, that certain conditions will be fulfilled or that a product will meet specified standards. Often functions as a legal or contractual obligation to provide a refund or repair if the subject fails to perform.
The new television comes with a two-year guarantee.
The contractor provided a written guarantee that the roof would not leak for at least ten years.
While the manufacturer offers a lifetime guarantee on the hardware, the fine print reveals that this protection does not extend to damage caused by regular wear and tear.
From Old French guarantie (perhaps via a later Spanish garante), from the verb guarantir (“to protect, assure, vouch for”), ultimately from Old Frankish warjand, warand (“a warrant”), or from guaranty. Doublet of guaranty and warranty.
Often takes the preposition 'on' or 'for' when referring to products, and 'that' when introducing a clause.
The shop gave me a 12-month warranty guarantee.The shop gave me a 12-month guarantee.Learners often combine 'warranty' and 'guarantee' into a single phrase, but they are usually synonyms used separately.