monomial

A monomial is a polynomial made of just one piece — a single term, with no plus or minus signs joining things together. Think of it as one solid building block before you start stacking: 5x^3, -7, or 2xy are each a monomial all on their own.

Formally, a monomial is a product of a coefficient (a number) and variables raised to non-negative integer powers. The prefix mono- means one, so a monomial is the one-term member of the polynomial family. The number 4 alone is a monomial, and so is the lone variable x.

Watch the boundary: 5x + 3 is not a monomial, because the plus sign splits it into two terms — that makes it a binomial. And 5/x is not a monomial at all, since negative or fractional exponents are forbidden, just as with any polynomial.