Relation algebra refers to a mathematical system used to manipulate binary relations, which are a set of ordered pairs. There are several synonyms that can be used to describe relation algebra, which include relational calculus, relational algebraic calculus, algebra of relations, and relational matrix theory. These alternative terms are often used interchangeably depending on the context and purpose of the application. They all share a common focus on the study and analysis of relationships and how they interact with one another in mathematical systems. The study of relation algebra can be applied across a wide range of fields, including computer science, artificial intelligence, and linguistics.