In the field of set theory a superset is a set that contains all the elements of another set. It is the opposite of subset.
More formally, set A is a superset of set B iff all elements contained in B are also contained in A. This would be written A ⊃ B.
For example, if A = {a,b,c,d} and B = {a,c}, then A is the superset of B.
Interesting things to note about superset:
- Every set is the superset of itself. (A contains everything A contains, doesn't it?)
- Every set is the superset of the empty set. This is sometimes called the null set or written ∅ (∅ in HTML).
See also: proper superset, subset, subset (math).