WordWeb Online

1. Become or cause to become soft or liquid
   "The giant iceberg unfroze over the years during the global warming phase";
   - dissolve, thaw, unthaw [N. Amer], dethaw, melt
    
2. Make (assets) available
   "unfreeze the holdings in the dictator's bank account";
   - unblock, free, release

Derived forms: unfreezing, unfreezes, unfroze, unfrozen

Type of: flux, issue, liquefy, liquify, supply

Antonym: freeze