guarantor
/ˌgærənˈtɔː(r)/noun
1- a person, organization, or thing that gives or acts as a guarantee起保证作用的人（或组织、事物）：
the role of the police as guarantors of public order.
警察作为公共秩序保障者的作用。
1.1
- Law a person or organization who provides a guaranty【律】担保人。