exponential

American  

[ek-spoh-nen-shuhl, -spuh-] / ˌɛk spoʊˈnɛn ʃəl, -spə- /

adjective

1. of or relating to an exponent or exponents.

2. Mathematics.

   1. of or relating to the constant e.

   2. (of an equation) having one or more unknown variables in one or more exponents.

3. rising or expanding at a steady, rapid rate.

   a city experiencing exponential growth.

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noun

1. Mathematics.

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

   2. any positive constant raised to a power.

exponential British  

/ ˌɛkspəʊˈnɛnʃəl /

adjective

1. 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

2.  exp.  maths raised to the power of e, the base of natural logarithms

3. of or involving an exponent or exponents

4. informal very rapid

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noun

1. maths an exponential function, etc

exponential Scientific  

/ ĕk′spə-nĕn′shəl /

1. Relating to a mathematical expression containing one or more exponents.

2. ◆ 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.

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Other Word Forms

• exponentially adverb
• nonexponential adjective

Etymology

Origin of exponential

First recorded in 1695–1705; exponent + -ial

Explanation

Exponential describes a very rapid increase. An exponential rise in the number of first graders with head lice might be a result of all the hat sharing that's gone on lately. Exponential is also a mathematical term, meaning "involving an exponent." When you raise a number to the tenth power, for example, that's an exponential increase in that number. When your next door neighbor describes the exponential growth of her rose bushes or the exponential increase in members of her book group, she means that there's been a sharp, fast expansion of both things.

Example Sentences

Monday morning has recaptured its 21 day exponential moving average, which is a solid momentum gauge.

From Barron's • Mar. 16, 2026

Momentum is also deteriorating, and support at the 21-day exponential moving average has faded, a line that had provided consistent support since the April lows.

From Barron's • Feb. 27, 2026

Noting the exponential growth of transactions in the last two years, one recent industry report estimates the global number of users has quadrupled to 15 million.

From The Wall Street Journal • Feb. 16, 2026

"My screen time has been exponential these past couple of weeks because I just love seeing people reacting to it," the 36-year-old says.

From BBC • Feb. 16, 2026

It’s been estimated that, because of the exponential growth of the world’s population, between 10 and 20 percent of all the human beings who have ever lived are alive now.

From "Innumeracy: Mathematical Illiteracy and Its Consequences" by John Allen Paulos