1. plural of billionth; parts that are each one of a billion equal parts of something

Examples

• The computer can measure time in billionths of a second.
• Scientists detected concentrations in the billionths.
• The precision instrument measures down to billionths of a meter.
• Pollutant levels were found in the billionths per liter.
• The atomic clock is accurate to billionths of a second.
• Chemical traces were present in billionths of the sample.