👉 A cancellus is a term used in mathematics, particularly in algebraic geometry and number theory. In these fields, it refers to a special kind of line that divides a plane into two regions called "cancellations." The term originates from the Greek word "cancella," which means "to split" or "to divide." The term "cancellus" is derived from this meaning and can be applied to any line that divides a plane into two regions. These regions are known