noun

A billion is a very big number. It is 1,000,000,000. That means it is one thousand million. You can think of it like this: if you had one million blocks, and you stacked them up, it would be a tower one billion blocks high!

Example

1. Apple just announced that it has made a record-breaking profit of over $30 billion.
2. The United States government has allocated a billion dollars to research renewable energy resources.
3. The world's population is expected to reach 9 billion by 2050.