n. 25B6; noun
all repairs have a one-year guarantee : WARRANTY, warrant.
a guarantee that the hospital will stay open : PROMISE, assurance, word (of honour), pledge, vow, oath, bond, commitment, covenant.
banks usually demand a personal guarantee for loans : COLLATERAL, security, surety, guaranty, earnest.
25B6; verb
he agreed to guarantee the loan : UNDERWRITE, put up collateral for.
can you guarantee he wasn't involved? : PROMISE, swear, swear to the fact, pledge, vow, undertake, give one's word, give an assurance, give an undertaking, take an oath, cross one's heart (and hope to die); archaic plight.