Formal verification is the process of using mathematical methods to prove the correctness of a design or system. There are several synonyms that can be used to describe this process. One such synonym is "mathematical verification," which refers to the use of formal methods to prove the correctness of a design or system. Another synonym for formal verification is "formal methods," which is a broader term that encompasses various mathematical techniques used to verify the correctness of software and hardware designs. Other synonyms for formal verification include "verification by formal reasoning" and "rigorous verification," both of which refer to the use of logical reasoning to verify the correctness of a system design.