(mathematics) Any function that has an exponent as an independent variable.

Relating to an exponent.

(mathematics) Expressed in terms of a power of e.

(mathematics) Characterised by a rate of change that is proportional to the value of the varying quantity, or, equivalently, by a doubling or halving over successive fixed intervals of time or other parameter.

(loosely) Characterised by a very rapid rate of change, especially increase.