Stitch up is a term that is usually used to mean to sew or stitch something together. However, it can also be used as a slang term with negative connotations, meaning to deceive or betray someone. There are several synonyms for this term, including hoodwink, deceive, swindle, dupe, double-cross, trick, and cheat. These words can be used interchangeably with stitch up to convey the same meaning. It is important to choose the right word depending on the context and the intended tone of the message. While some synonyms may sound harsher than others, they are still important to express the intended meaning.