billion
number /ˈbɪljən/
/ˈbɪljən/
- (abbreviation bn)1 000 000 000; one thousand million
- Worldwide sales reached 2.5 billion.
- half a billion dollars
- They have spent billions on the problem (= billions of dollars, etc.).
- a billion, billions (of…)(informal) a very large amount
- Our immune systems are killing billions of germs right now.
- (British English, old-fashioned) 1 000 000 000 000; one million million synonym trillion
Word Originlate 17th cent.: from French, from million, by substitution of the prefix bi- ‘two’ for the initial letters.