Monomial/Definition

For a set of variables ${\displaystyle {}X_{1},\ldots ,X_{n}}$ and an ${\displaystyle {}n}$-tuple ${\displaystyle {}(\nu _{1},\ldots ,\nu _{n})\in \mathbb {N} ^{n}}$, an expression of the form ${\displaystyle {}X_{1}^{\nu _{1}}\cdots X_{n}^{\nu _{n}}}$ is called a monomial in the ${\displaystyle {}X_{i}}$.