The word "Refunder" can be replaced by several synonyms that convey similar meanings. The term "reimburser" is one such synonym, which pertains to the act of paying back money that was spent. Another synonym for "refunder" is the word "repayer," which essentially refers to paying someone back for something. The word "restitutor" is another option, which refers to someone who restores something that was lost or taken away. Additionally, the term "remitter" can also be used to indicate a person who refunds payment to someone. These synonyms provide alternative options for expressing the same concept as the word "refunder".