1. Give surety or assume responsibility
   "The company guaranteed the quality of their products";
   - vouch
    
2. Make certain in the future
   "Preparation will guarantee success!";
   - ensure, insure, assure, secure
    
3. Promise to do or accomplish
   "guarantee to free the prisoners";
   - undertake
    
4. Stand behind and guarantee the quality, accuracy, or condition of
   "The dealer guarantees all the cars he sells";
   - warrant

1. An unconditional commitment that something will happen or that something is true
   "there is no guarantee that they are not lying"
    
2. A written assurance that some product or service will be provided or will meet certain specifications
   "The car came with a five-year guarantee";
   - warrant, warranty
    
3. A collateral agreement to answer for the debt of another in case that person defaults
   "The parent company provided a guarantee for its subsidiary's loan";
   - guaranty

Derived forms: guarantees, guaranteeing, guaranteed

Type of: assurance, assure, back, collateral, endorse, indorse [rare], pledge, plight [archaic], plump for, promise, support, verify

Encyclopedia: Guarantee