In mathematics, a monomial is, roughly speaking, a polynomial which has only one term. Two definitions of a monomial may be encountered: In mathematics, a monomial is, roughly speaking, a polynomial which has only one term. Two definitions of a monomial may be encountered: In the context of Laurent polynomials and Laurent series, the exponents of a monomial may be negative, and in the context of Puiseux series, the exponents may be rational numbers. Since the word 'monomial', as well as the word 'polynomial', comes from the late Latin word 'binomium' (binomial), by changing the prefix 'bi' (two in Latin), a monomial should theoretically be called a 'mononomial'. 'Monomial' is a syncope by haplology of 'mononomial'.