The word span has several meanings in mathematics. In linear algebra, the vector space span of a set of vectors is the set of their finite linear combinations. In geometry, the geometric span of a finite point set is its greatest pairwise distance.
The set span of a finite set of real numbers is the difference between its maximum and minimum. For a polynomial, the polynomial span is the difference between its highest and lowest degrees, while the link span is the corresponding degree difference for the bracket polynomial of a link diagram.
