Base

The number being repeatedly multiplied in a power; in $4^3$, the base is 4.

The number or expression that is raised to a power; in $5^3$, the base is $5$.

The number or algebraic quantity to which an index applies; in $a^2$, the base is $a$.

The number that is repeatedly multiplied by itself in a power; in $5^3$, the base is $5$.

The number or algebraic expression to which an index applies. In $a^3$, the base is $a$.

The fixed number being raised to a power in an exponential expression; $k$ is the base in $k^x$.

The number or expression being raised to a power; in $a^n$, the base is $a$.

The number that is repeatedly multiplied in a power; in $3^4$, the base is $3$.