billion

American  

[bil-yuhn] / ˈbɪl jən /

noun

billions, plural billion plural

1. a cardinal number represented in the U.S. by 1 followed by 9 zeros, and in Great Britain by 1 followed by 12 zeros.

2. a very large number.

   I've told you so billions of times.

---

adjective

1. equal in number to a billion.

billion British  

/ ˈbɪljən /

noun

1. one thousand million: it is written as 1 000 000 000 or 10 ⁹

2. (formerly, in Britain) one million million: it is written as 1 000 000 000 000 or 10 ¹²

3. (often plural) any exceptionally large number

---

determiner

1. (preceded by a or a cardinal number)

   1. amounting to a billion

      it seems like a billion years ago

   2. ( as pronoun )

      we have a billion here

Other Word Forms

Derived Forms

• billionth
  adjective

Inflected Forms

Nouns

• billion
  plural
• billions
  plural

Etymology

Origin of billion

1680–90; < French, equivalent to b ( i )- bi- ¹ + -illion, as in million

Compare meaning

How does billion compare to similar and commonly confused words? Explore the most common comparisons:

• billion vs. trillion

Explanation

A billion is 1,000,000,000. There are over 7 billion people in the world, the last time we checked. While billion may sounds like a made-up number like zillion — which just means a lot — it's a very real number, specifically 1,000,000,000. That's a pretty hard number to imagine, but one way to think of it is as a thousand millions. If you have a billion dollars, you're very rich: a billionaire. Money spent by the government is often measured in billions. In England, this word often refers to a different number: 1,000,000,000,000, or one million millions.

Example Sentences

See Examples For:

billion billions

The company aims to cut annual costs by 1.9 billion pounds by 2029, leading to a stable or improving operating margin coinciding with the patent-expiration period for HIV drug dolutegravir between 2028 and 2030.

From The Wall Street Journal ● Jul. 29, 2026

The company had forecast bookings of 20 billion euros, but warned earlier this month that Germany’s decision to scrap a project to procure F126 frigates would dent orders.

From The Wall Street Journal ● Jul. 29, 2026

Analysts had forecast 3.16 billion euros in revenue, according to Vara Research.

From The Wall Street Journal ● Jul. 29, 2026

The payroll and workplace-administration company said it expects revenue to rise 5% to 6% in the year ahead, which would come out to roughly $23 billion to $23.2 billion.

From The Wall Street Journal ● Jul. 29, 2026

By early 2005 Howie Hubler had found a sufficient number of fools in the market to acquire 2 billion dollars’ worth of these bespoke credit default swaps.

From "The Big Short" by Michael Lewis

Last week, GM also lifted its full-year profit forecast and said it plans to invest billions into boosting U.S. production of its largest vehicles.

From The Wall Street Journal ● Jul. 28, 2026

Talarico denied the charge at his own news conference Wednesday, saying he’d voted for billions of dollars in law enforcement funding as a member of the Legislature.

From Salon ● Jul. 28, 2026

"We are taking in a lot of money. Billions and billions of dollars," he said.

From Barron's ● Jul. 27, 2026

Now they fear that AI technology - which China is pouring billions of dollars into - is providing simple, accessible tools that can be used to trick the public.

From BBC ● Jul. 27, 2026

But elsewhere, on older worlds, where life has evolved billions of years earlier than on Earth, perhaps they know 1020 bits or 1030—not just more information but significantly different information.

From "Cosmos" by Carl Sagan