I have to go after Steve Mercer, she thought for probably the billionth time.
我一定要去找史蒂夫·默瑟,这大概是她第十亿次这样想了。
...a billionth of a second.
...十亿分之一秒。
Thus time and time's relativity are measurable by any hourglass, alarm clock, or atomic clock that can measure a billionth of a second.
因此,时间和时间的相对性可以用任何沙漏、闹钟或原子钟来测量,其中原子钟可测量出十亿分之一秒。
A nanometre is a billionth of a metre.
十亿分之一米是一纳米。