1. the number 1,000,000,000 (one thousand million)
Usage: American English
2. the number 1,000,000,000,000 (one million million)
Usage: British English; traditional
3. a very large number or amount
Usage: informal

1. used to indicate the number 1,000,000,000

Examples

• The company is worth over three billion dollars.
• China has more than a billion people.
• The government spent billions on infrastructure.
• I’ve told you a billion times to clean your room.
• The national debt reached two billion pounds.
• There are billions of stars in the galaxy.
• The project will cost several billion euros.