billionth

1 of 2

adjective

bil·​lionth ˈbi(l)-yən(t)th 

1

: being number one billion in a countable series see Table of Numbers

2

: being one of a billion equal parts into which anything is divisible

billionth

2 of 2

noun

bil·​lionth ˈbi(l)-yən(t)th 

plural billionths

1

: number one billion in a countable series

2

: the quotient of a unit divided by one billion : one of a billion equal parts of anything

Word History

Etymology

Adjective

billion + -th

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Rhymes for billionth

• millionth