surety in WordNet English dictionary

1. one who provides a warrant or guarantee to another
   guarantor  surety  warrantor  warranter 
   
2. a prisoner who is held by one party to insure that another party will meet specified terms
   hostage  surety 
   
3. a guarantee that an obligation will be met
   security  surety 
   
4. property that your creditor can claim in case you default on your obligation
   "bankers are reluctant to lend without good security"
   security  surety 
   
5. something clearly established
   surety