Pronunciation: (ik-spō'nunt or, esp. for 3, ek'spō-nunt),[key] —n. 1. a person or thing that expounds, explains, or interprets: an exponent of modern theory in the arts. 2. a person or thing that is a representative, advocate, type, or symbol of something: Lincoln is an exponent of American democracy. 3. Math.a symbol or number placed above and after another symbol or number to denote the power to which the latter is to be raised: The exponents of the quantitiesxn, 2m, y4, and 35are, respectively, n, m, 4, and 5.