1. One that expounds or interprets.
2. One that speaks for, represents, or advocates: Our senator is an exponent of free trade.
3. Abbr. exp Mathematics A number or symbol, as 3 in (x + y)3, placed to the right of and above another number, symbol, or expression, denoting the power to which that number, symbol, or expression is to be raised. Also called power.
[Latin expnns, expnent-, present participle of expnere, to expound; see expound.]
Expository; explanatory | adj.