It is used for the ratio of the circumference of a circle to its diameter.

pi代表着圆周到直径的。

It's also the ratio of a circle's circumference divided by its diameter.

它也是圆周长除以直径的率。

That's one one-thousandth the width of a human hair.

相当于人类发丝直径的千分之一。

That is about the distance of one-fifth of a full moon.

这一距离约为满直径的五分之一。

In the simplest definition, pi is the ratio of a circle's circumference to its diameter.

在最简明的定义中，π是圆周长与其直径的率。

The fragment of rock is extremely small, measuring just twice the diameter of a human hair.

这块岩石碎片很小，只有人头发直径的两倍大小。

The one used in this project is the biggest in diameter developed by China.

这个项目中使用的是中国开发的最大直径的（盾构机）。

It is also more than nine times the diameter of Earth's moon.

它的直径也是球的九倍多。

Meanwhile, axons with larger diameters offer less internal resistance.

同时，直径较长的轴突拥有较小的内部阻力。

These events occur on a colossal scale-the magnetosphere extends outward about 10 times the diameter of the earth.

这些是庞大规模事件——磁层向外延伸的距离约为地球直径的10倍。

Luna's diameter is roughly one quarter the size of Earth, measuring 2,160 miles.

球的直径大约为地球的四分之一，2160英里。

It's about tens of meters in diameter.

它的直径大概有几十米。

Mars is just half the diameter of Earth, meaning its core cooled more quickly.

火星的直径只有地球的一半，这意味着它的核心冷却得更快。

It is extremely dense, however, because it is only 1.5 times the Earth's width.

然而，它的密度极大，因为它的直径只有地球的1。5倍。

They're up to 8.4 meters in diameter.

它们的直径达到8.4米。

You measured the diameter of his suspicious mole yesterday.

你昨天还测量了他可疑痣的直径。

Number four, the meteor was blank meters in diameter.

第四题，陨石的直径有多少米。

The Observable Universe is 93 billion lightyears in diameter.

可观测宇宙的直径为930亿光年。

The largest is called Caloris Basin, a whopping huge impact feature 1600 kilometers across.

其中最大的被称为卡洛里盆地，是在一个巨大的冲击力下形成的直径1600千米的陨石坑。

Each of the meatballs should be about one and a half inches in diameter.

每个肉丸的直径应该在1.5英寸左右。