/əˌprɑːk.səˈmeɪ.ʃən/
an estimate of a number or an amount that is almost correct, but not exact 近似值；粗略估算
That’s just an approximation, you understand.
你知道那仅仅是近似值。
~ (of/to sth) a thing that is similar to sth else, but is not exactly the same 类似事物
Our results should be a good approximation of the true state of affairs.
我们的结果应该和实际情况相当接近。