Definition from Wiktionary, the free dictionary
See also: venndiagram
Named after John Venn (1834–1923), British mathematician and philosopher.
- (set theory) A diagram representing some sets by contours of closed shapes, such as circles or ellipses (and sometimes also the universal set as a rectangle enclosing all of these shapes), and indicating the relationships between the sets: by overlapping the shapes to show that the corresponding sets have a non-empty intersection, and by possibly (but not necessarily) enclosing all of the sets (which are proper subsets of the universal set) within a universal set (represented typically by a rectangle); such that the total number of simply connected regions is , where n is the number of depicted sets which are proper subsets of the universal set.
diagram representing sets by circles