[ek-spoh-nen-shuh l, -spuh-]


of or relating to an exponent or exponents.
  1. of or relating to the constant e.
  2. (of an equation) having one or more unknown variables in one or more exponents.
rising or expanding at a steady and usually rapid rate:a city experiencing exponential growth.


  1. the constant e raised to the power equal to a given expression, as e3x, which is the exponential of 3x.
  2. any positive constant raised to a power.

Origin of exponential

First recorded in 1695–1705; exponent + -ial
Related formsex·po·nen·tial·ly, adverbnon·ex·po·nen·tial, adjectivenon·ex·po·nen·tial·ly, adverb
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for exponential

Contemporary Examples of exponential

Historical Examples of exponential

  • The energy it would receive from the Sun as it approached, an exponential curve.

    The Leech

    Phillips Barbee

  • It multiplies and surges to its fulfillment at an exponential rate.

    The Demi-Urge

    Thomas Michael Disch

  • The inevitable outcome is an exponential explosion in computing and networking power.

    After the Rain

    Sam Vaknin

British Dictionary definitions for exponential



maths (of a function, curve, series, or equation) of, containing, or involving one or more numbers or quantities raised to an exponent, esp e x
maths raised to the power of e, the base of natural logarithmsSymbol: exp
of or involving an exponent or exponents
informal very rapid


maths an exponential function, etc
Derived Formsexponentially, adverb
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for exponential

1704, from exponent + -al (1). As a noun, from 1784. Related: Exponentially.

Online Etymology Dictionary, © 2010 Douglas Harper

Science definitions for exponential



Relating to a mathematical expression containing one or more exponents.♦ Something is said to increase or decrease exponentially if its rate of change must be expressed using exponents. A graph of such a rate would appear not as a straight line, but as a curve that continually becomes steeper or shallower.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.