Definitions
1.NounAnything that assures a certain outcome."Can you give me a guarantee that he will be fit for the match?"
2.NounA legal assurance of something, e.g. a security for the fulfillment of an obligation.
3.NounA written declaration that a certain product will be fit for a purpose and work correctly; a warranty."The cooker comes with a five-year guarantee."
4.NounThe person to whom a guarantee is made.
5.NounA person who gives such a guarantee; a guarantor.
6.VerbTo give an assurance that something will be done right.
7.VerbTo assume or take responsibility for a debt or other obligation.
8.VerbTo make something certain."The long sunny days guarantee a good crop."