trillion

noun

tril·​lion ˈtri(l)-yən 

1

: a number equal to 1,000 times one billion see Table of Numbers

2

: an indeterminately large number

a trillion mosquitoes out tonight

trillion adjective

trillionth

ˈtri(l)-yən(t)th 

adjective or noun

Examples of trillion in a Sentence

Recent Examples on the Web

During training, the model ingests vast amounts of text and other data while an algorithm adjusts billions or trillions of numerical dials—the weights—until the system can predict and eventually generate humanlike content. — Jacek Krywko, Scientific American, 23 July 2026

The government is issuing boatloads of Treasurys to pay for our huge budget deficit and to refinance trillions of dollars in existing debt that is coming due. — Steve Forbes, Forbes.com, 21 July 2026

The federal government has been running on a hamster wheel of debt by refinancing trillions of dollars every month with trillions more in fresh borrowing that comes due in a few months. — Jason Ma, Fortune, 20 July 2026

The impact flung trillions of tons of debris into the sky, and much of it headed right into that yawning atmosphere and into Earth’s orbit. — Nancy Walecki, The Atlantic, 17 July 2026

Word History

Etymology

French, from tri- + -illion (as in million)

First Known Use

1745, in the meaning defined at sense 2

Rhymes for trillion

• billion
• million
• pillion
• castilian
• civilian
• cotillion
• pavilion
• postilion
• quadrillion
• reptilian
• vermilion
• vermillion

Kids Definition

trillion

noun

tril·​lion ˈtril-yən 

1

: a number equal to 1,000 times one billion see number

2

: a very large number

a trillion mosquitoes out tonight

trillion adjective

trillionth

-yən(t)th 

adjective

trillionth noun