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

The Internet Archive has been responsible for saving and providing access to trillions of websites over the past 30 years. —Devika Rao, TheWeek, 20 Apr. 2026

Over the coming decade, the cost of the epidemic is projected to number in the trillions. —The Editorial Board, Chicago Tribune, 20 Apr. 2026

Last year was a record-breaking one for international tourism, injecting trillions of dollars into the global economy and supporting millions of jobs. —Tristan Bove, Fortune, 17 Apr. 2026

Our gut microbiome is made up of trillions of bacteria that influence digestion, immunity and overall health. —Leeann Weintraub, Daily News, 15 Apr. 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