noun
Mathematical term for the power to which a number or expression is raised.
この式では、x のべき指数は 3 です。
In this expression, the exponent of x is 3.
指数 is a broader term meaning 'index' or 'exponent' in various contexts (e.g., stock index, exponential function). べき指数 specifically refers to the exponent in a power expression.
Compound of べき (power, exponent) and 指数 (index, exponent). The kanji 冪 and 羃 are older forms for 'power' in mathematics.