billionth

Từ điển WordNet v3.1 - WordNet Dictionary

I - noun

1. position 1,000,000,000 in a countable series of things
• Regions:
United States, United States of America, America, the States, US,
U.S., USA, U.S.A.
• Hypernyms:
rank
2. one part in a billion equal parts
• Syn:
one-billionth
• Hypernyms:
common fraction, simple fraction

II - adjective

the ordinal number of one billion in counting order
• Similar to:
ordinal