The word "mendment" may not be familiar to everyone, but fear not, for there are several synonyms that can come to the rescue. One suitable alternative is "improvement", which suggests enhancing or refining something. Another synonym is "amendment", which refers to making changes or modifications, particularly within legal or legislative contexts. "Revision" is yet another option, implying a reexamination and alteration of something, such as written work or plans. Additionally, the word "alteration" can be used to denote modifying or adjusting something in a subtle or substantial manner. So, when "mendment" doesn't quite fit the bill, these synonyms can step in to express similar ideas in a more familiar way.