Simple Definition of quadrillion

from our Learner's Dictionary

quadrillion

noun

kwɑˈdrɪljən How to pronounce quadrillion (audio)
plural quadrillion or quadrillions
: the number 1,000,000,000,000,000 : one thousand trillion

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“Quadrillion.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/quadrillion. Accessed 8 Apr. 2026.

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