Fewnomial

A fewnomial is a multivariate polynomial having relatively few nonzero monomials compared with its polynomial degree. For example,

has very high polynomial degree but only three monomials.

Fewnomial theory bounds the number and topology of real solutions of systems of polynomial equations in terms of the number of monomials, largely independently of their degrees. It was developed by Khovanskii and includes results for systems of Laurent polynomials.