qua·​dril·​lion | \kwä-ˈdril-yən \

Definition of quadrillion 

US : a number equal to 1 followed by 15 zeros — see Table of Numbers also, British : a number equal to 1 followed by 24 zeros — see Table of Numbers

Keep scrolling for more

Other Words from quadrillion

quadrillion adjective
quadrillionth \ kwä-​ˈdril-​yən(t)th \ adjective or noun

Examples of quadrillion in a Sentence

Recent Examples on the Web

The other three quarters are cars and trucks using gasoline, factories using quadrillions of British thermal units to forge metals and refine petroleum, and buildings heated by gas or propane. Nathanael Johnson, WIRED, "Where Can Climate Activists Find Common Ground?," 9 July 2018 But literally quadrillions of proton collisions in the collider later, nothing new has emerged. Jason Daley, Smithsonian, "Researchers Find More Evidence for the Higgs Boson," 10 July 2018 That's as many as 20 quadrillion individual bugs munched by birds annually, a scientific study reports. Doyle Rice, USA TODAY, "Yum! Birds eat up to 550 million tons of insects each year," 9 July 2018 That's as many as 20 quadrillion individual bugs munched by birds annually, a scientific study reports. Doyle Rice, ajc, "Yum! Birds eat up to 550 million tons of insects each year," 9 July 2018 The weight of the atmosphere is estimated to be about 5.75 quadrillion (5,750,000,000,000,000) tons. Tom Skilling, chicagotribune.com, "Ask Tom: How heavy is the Earth's atmosphere?," 27 June 2018 This is how the machine's developers at Tennessee's Oak Ridge National Laboratory put it: Summit can perform 200 quadrillion calculations per second. Josh Axelrod, CNN, "This computer can do more calculations per second than the world's population could do in a year," 9 June 2018 Oak Ridge says its new baby can deliver a peak performance of 200 quadrillion calculations per second (that’s 200 followed by 15 zeros) using a standard measure used to rate supercomputers, or 200 petaflops. Tom Simonite, WIRED, "The US Again Has World’s Most Powerful Supercomputer," 8 June 2018 BlueTides, for example, runs on Blue Waters—a supercomputer at the University of Illinois in Urbana that can perform 13 quadrillion calculations per second. Adrian Cho, Science | AAAS, "Galaxy simulations are at last matching reality—and producing surprising insights into cosmic evolution," 30 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'quadrillion.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

See More

First Known Use of quadrillion

circa 1690, in the meaning defined above

History and Etymology for quadrillion

French, from Middle French, from quadri- + -illion (as in million)

Keep scrolling for more

Learn More about quadrillion

Share quadrillion

Statistics for quadrillion

Last Updated

2 Oct 2018

Look-up Popularity

Time Traveler for quadrillion

The first known use of quadrillion was circa 1690

See more words from the same year

Keep scrolling for more

More Definitions for quadrillion



English Language Learners Definition of quadrillion

: the number 1,000,000,000,000,000 : one thousand trillion

More from Merriam-Webster on quadrillion

See words that rhyme with quadrillion

Comments on quadrillion

What made you want to look up quadrillion? Please tell us where you read or heard it (including the quote, if possible).


obstinately defiant of authority

Get Word of the Day daily email!

Test Your Vocabulary

Autumn Words of the Day 2018

  • a-top-down-image-of-road-through-an-autumn-forest
  • Which is a synonym of fugacious?
Name That Thing

Test your visual vocabulary with our 10-question challenge!

Syn City

Test Your Knowledge - and learn some interesting things along the way.


Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!