The definition of a guarantee is a promise that something will happen.
(noun)An example of guarantee is a document stating that a new barbecue grill will be repaired free of charge for the first two years after purchase.
Guarantee is defined as to state with confidence that something will happen.
(verb)An example of guarantee is for a store to sign a document stating that they will repair a new computer free of charge for three years after purchase.
See guarantee in Webster's New World College Dictionary
noun
Origin: altered < guaranty, after words ending in -ee
transitive verb guaranteed, guaranteeing
See guarantee in American Heritage Dictionary 4
noun
Origin:
Origin: Alteration of Middle English garant, warranty
Origin: , from Old French; see guaranty
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