To agree, verify or concur; to answer positively.
To make firm; to confirm, or ratify; especially (law) to assert or confirm, as a judgment, decree, or order, brought before an appellate court for review.
To state under a solemn promise to tell the truth which is considered legally equivalent to an oath, especially of those who have religious or other moral objections to swearing oaths; also solemnly affirm.
To assert positively; to tell with confidence; to aver; to maintain as true.
To support or encourage.
To make something certain.
To give an assurance that something will be done right.
To assume or take responsibility for a debt or other obligation.
The person to whom a guarantee is made.
A person who gives such a guarantee; a guarantor.
A legal assurance of something, e.g. a security for the fulfillment of an obligation.
More specifically, a written declaration that a certain product will be fit for a purpose and work correctly; a warranty
Anything that assures a certain outcome.